|
How better to learn lessons on tyres than by inspecting hands-on the tyres on the rigs on our roads. That's exactly what we do in our Brake and Tyre Watch project, the last of which we staged in March using the Centurion test centre in Tshwane. As with our last project staged in Middelburg, Marcus Haw and his team from Bridgestone inspected the rigs taken off the road and in this series of photographs and captions, we bring you what
FleetWatch considers to be one of the most comprehensive 'lesson features' published on real on-the-road tyre faults. This is not a quick read and as Editor of
FleetWatch, I urge operators to take time out to study the photographs and accompanying captions and to heed what Marcus Haw is getting across. It can only lead to improvements because what we picked up on the day is cause for grave concern. Not only are cost factors highlighted here but more importantly, safety factors. It's bad out there - worse than we ever thought!
 |
|
The ‘Safety Warriors’ of
Brake & Tyre Watch gather round to inspect another rig from top to
bottom.
|
| 01
The two tyres shown here, and fitted together, are not safe for two reasons. The one is that so much rubber is missing that normal performance expectations cannot be applied here. The rubber to void ratio, normally a measure of how much footprint area is actually in contact with the road surface, is completely changed because of the chunks ripped out. Because of this, the twin tyres in the position will have seriously compromised grip, both in setting the vehicle in motion and in retarding that motion. Wet braking will definitely be reduced and any loose surface grip or traction too. The other reason that the tyres are no longer safe is that in many areas, the steel stabiliser belts have been exposed. Once these are exposed - even in very small areas - contamination and subsequent corrosion take place. The bonding of rubber to steel is one of the more sensitive areas in tyre construction. When contamination and corrosion take place - especially in so many possible areas - the chances of the belts separating are greatly increased and if a belt, or part or all of the belt package comes loose, the bits and pieces can do a lot of damage. This damage can include any vehicle behind or next to those tyres
|
|
|
|
02
Let's ignore the missing mud-flap and the bent mudguard which, if it bends any further will destroy the tyres. The problem here is more subtle but over the next few months will work out to be quite expensive for the owner. Notice the feathering visible on the tread rib edges, most noticeable on the left tyre in the photograph. This is an indication that the alignment, or axle parallelism, of this axle is out by the proverbial mile. This will wear the tyres on this axle off at an angle and will increase the wear rate by a huge amount. The real expense though, comes from the knock-on effect this has on the other tyres on the vehicle. This axle is effectively steering the vehicle now and those tyres on the other axles have to correct the directional plane of the vehicle. Irregular wear and accelerated wear rate on all tyres is to be expected.
|
| 03
On this tri-axle trailer, a number of tyre problems exist which can affect both safety and running costs. The tyres are all mismatched, the centre axle has got drive axle tyres fitted which are not going to give their best performance since they were not designed to run on a trailing axle, and the inflation pressures are expected to vary quite considerably between all the tyres, even those fitted together. Note the irregular wear pattern on the outer tyre on the centre axle. This is an indication of a dimensional difference in the rolling circumference of the two tyres. Considering that they are the same make and type of tyre, and the rims were the correct width, the most likely reason behind the dimensional variance is because one was at a lower pressure than the other. The other tyres show similar indications but to lesser degrees. Anyone can see that this guy can afford to spend a bit extra on his tyres because he seems to be saving quite a bit on yellow visibility tape.
|
|
|
|
04 We have two concerns here. The most obvious is that the tyres are almost completely smooth. The second is that again, the wrong tyres are in the wrong position. These are drive axle tyres on a trailing axle, not necessarily a dangerous situation, but certainly not good practice. |
| 05 Tyre patterns mismatched, one tyre almost smooth and the other severely damaged. What is the reason, or the thinking behind a transporter actually believing it is acceptable to run tyres in this condition? In photo
5a one can see the extent of the damage. As explained in (1), once the steel belt is exposed, contamination and corrosion follow very quickly and the likelihood of belt failure is imminent. |
|
|
|
06 The rocker-arm on this trailer has broken off, and at some time, someone with a welding machine, and absolutely no welding knowledge or ability, has tried to weld it back on. Notice the positioning of the weld and where the rocker arm has moved to. It was actually moving back and forth. Now bear in mind that any movement in the suspension is directly transmitted to the tyres and irregular wear and accelerated wear rate is the only result. So now we know that this transporter has extra budget to waste on his tyres - but what of the safety involved here? If this is the type of repair work that is acceptable to the rig's owner, do you think he cares about other safety factors such as the maintenance on his brakes for example? Well as expected, he doesn't. This vehicle had no brakes either, so the lack of grip of his tyres was never going to be a concern. |
| 07 Same rig, same type of tyre, same condition and the owner thought it acceptable to let it loose among the morning traffic between Tshwane and Johannesburg. And in our ignorant belief and faith in human nature, we all thought it safe to let our families out on the same roads. The funny thing is (if you have a really warped sense of humour that is) the owner of this rig probably lets his family out on the same roads at the same time as his rigs too. How's that for a fatalistic attitude? Or is just plain stupidity? |
|
|
|
08 Still the same rig and the same situation. No need to say more, but it should really be pointed out that this is only an example of what is allowed on our roads. We need to re-look at the laws governing our traffic. Vehicles like this are out on our roads among us every day, and they wonder why the deaths on our roads are at the levels they are. Everyone, even the very transporters whose vehicles we were checking, are happy to shout and throw criticism at the taxis on our roads - and so they should as that is another industry which has little or no regard for human life. But while everyone is so concerned about the state of the taxis, they should bear in mind that the transport industry is as bad in their maintenance practices and the size and weight of their vehicles makes them a lot more dangerous. Now everyone is going to jump up and shout that not all transporters should be tarred with the same brush. Well guess what? I have seen some new taxis out there with very polite and friendly drivers too.
|
| 09 Roughly 60% of the wheels I checked at this Brake and Tyre Watch exercise were not fitted with valve caps of any description. A good steel valve cap can maintain a pressure of 800kPa and more, so even if the valve core should fail completely, the tyre remains safe. Even a non recommended plastic valve cap will at least keep the dirt and grime out of the valve and protect it from slow leaks. Transporters continue to pay in excess of R4 000 for a tyre, but won't spend the extra R2.00 odd for a decent steel valve cap. The logic escapes me. |
|
|
|
10 About 15% of the dual wheels I inspected were miss-mated so that it was impossible to access the inner valve. And, I didn't get to inspect every wheel myself so realistically, the percentages can be expected to be far higher. The ramifications of running dual wheels with differing pressures, and therefore differing rotational dimensions, were discussed in the last Brake and Tyre Watch so I won't go through it again now. It will come up again later anyway and we can discuss it then. Suffice to say that it is poor practice and apart from the safety considerations, it escalates running costs to ridiculous levels despite this being such an easy practice to correct and maintain. |
| 11 One may well ask why a tyre person would be showing, and commenting on, a photo of a spring pack. Well, the whole point is that all suspension and chassis, wheel and suspension components have a very direct influence on the life of tyres. In this case, notice the angle of the leaves in the spring pack shown here. This is on the front axle of a small tipper and while it was quite obviously severely overloaded for the vehicle in question, it turned out to be within legal parameters. The tyres also were in fact able to take the load with some spare capacity. The problem is that in a situation like this, we need to re-assess the legalities involved because the vehicle that left the test station quite legally was, in fact, a very unsafe vehicle. This vehicle gets discussed in the following few photos as well, and the reasons I say it was unsafe will become clear as we go on. |
|
 |
 |
 |
 |
|
13
Here is the left spring pack showing again that the front axle is substantially overloaded.
13a
This is the right side spring pack. Both sides of the vehicle are equally overloaded.
13b
Notice here, still on the same vehicle, how the rear spring hanger and blade end and bush are hard up against
the cross-member at the back of the pack.
13c
Here the left side shows a huge gap between the rear of the spring pack and the same cross-member. So the
whole axle is chronically out of square to the chassis, having being out under such stress through the overload.
So because the vehicle is so severely overloaded on the front axle, many components are under such severe
stress that component breakage is imminent. Something on this vehicle is going break very soon and an
accident through the breakage is very likely. While the tyres are within their load range quite comfortably, they are not going to last because of the angle of the axle. Further to this is the fact that, with the severe stress being placed on all the front suspension components, nothing can be working as it should be and the possibility of bending and twisting taking place is highly probable. The tyres then would be stressed by the various angle changes taking place during turns, braking etc. So we end up with a LEGAL vehicle, which is so stressed, something has to go - and an accident is a very real consideration.
|
| 14 We've already discussed the reasons why it is a good idea to fit good steel valve caps. However, I thought it worthwhile to show the irony of the logic in the thinking of our local transporters. You have to love it. Here the owner considers tyres a high enough priority to fit one of the best tyres available to his vehicle. This choice involves the decision of paying a premium price for premium quality. And then; save R1.60 or R2.00 on the fitting of a valve cap, put your tyre at the risk of a slow fatal leak through a contaminated valve core. It boggles the mind, doesn't it? Stupidity in excess is all around us. |
|
 |
15 Here is the perfect example of what happens when the inflation pressure of an inside tyre of a dual assembly is not correctly maintained. The irregular wear seen here, and closer up in
15a, is the result of the inner tyre being at a lower pressure than its mate, resulting in a variance of rotational dimensions. This is a particularly common problem and is more difficult to control than one would think. Bear in mind that heat increases tyre pressure, no matter what the cause of the heat. So, with the outer tyre being more consistently exposed to the sun, it generally is warmer than the inner, even when standing still. Usually the difference is not that great though and if the cold pressures of both tyres were correct, they would quickly balance out once moving. The inner tyre does however start out with a disadvantage and therefore the maintaining of their pressures is critical if you want the inner tyres to reach their potential life. |
| 16 This is an example of what I would like to see more of. Although this vehicle had obviously been well used - even the wheel rim flange edge showed damage - the general wheel maintenance discipline is such that the valves are both in good condition, placed at 180° from each other. Both are fitted with steel valve caps, and the inner is fitted with a well maintained valve extension. Proof of the value of this type of disciplined maintenance is the fact that both tyres, even the one on the bent rim, were wearing evenly as in fact were all the tyres on the vehicle. Far newer vehicles were seen during the day with far worse tyre wear just because this operator runs his operation with a professional approach. As said, this was an elderly and very well used vehicle but it breezed through the check with no problems found. |
|
|
|
17
Here again, is a very common problem found regularly on tube type wheels. It was also highlighted in our last Brake and Tyre Watch, but we'll go through it again for those who missed it. The problem here is that the valve stem is in constant contact with the brake drum. Obviously, the brake drum gets extremely hot. This heat is transmitted through the valve stem to the valve core. The valve core is simply a small non-return valve based on the action of a very small spring. This little spring looses its tension through extreme heat transmitted from the brake drum. Consequently, through the loss of tension in the spring the non-return valve opens and a slow but ever increasing leak develops, and the most common result is that the tyre and tube are destroyed. In a number of cases, where this chain of events involves a front, or steer tyre, an accident has resulted from the tyre failure.
|
| 18 Another case of a truck with one smooth and illegal tyre, and one almost smooth tyre fitted on one side of a truck. So the braking power of this axle is reduced by half at least. In this case, the tyres on the other side of the axle were not that great either, so in an emergency, especially in the wet, this vehicle cannot be expected to react in a safe and stable manner. |
|
|
|
19 Two problems can be seen here, both the result of poor or no maintenance, and an indication of an owner with a 'don't care' attitude and a lack of pride. One is the missing wheel nut which is quite obvious, but harder to see is that the inner wheel's valve is also jammed up against the brake drum - and is in a very poor condition. This type of thing is far too common, and the problem is that once you find something like this, it is usually a very good indication of the general condition of the vehicle. Most commonly, if one looks further, the vehicle is found to be poorly maintained all over and would not pass a roadworthy test. Safety is obviously of little concern to the owner, and it is these types of vehicles which should be unconditionally and permanently removed from the road. |
| 20 Same vehicle as above. What a mess! Different length studs haphazardly fitted to the bearing cap, washers used as spacers and grease, grime and muck all over. Fire the mechanic and take the operator's business licence away I say. What has this got to do with tyres though you ask? As mentioned earlier, all the chassis, suspension and wheel components affect the tyres to some degree. A wheel bearing not correctly maintained or adjusted has very direct effect on the tyre wear. Now can you imagine the idiot who assembled this mess taking the time to accurately adjust the wheel bearing? I doubt it. And with the bearing cap not seating correctly, grease escaping and dirt getting in, how long is the bearing going to last anyway? |
|
|
|
21
Spot the problem! See the scuff mark on the sidewall of the inner tyre. This is from a brick stuck between the two tyres. It needed a hammer and a tyre iron to get it out. Truck drivers should check for this type of problem each time they stop. The small stones stuck in the tread will most like get thrown out on the road, but it's a good idea for the driver to remove these as well. Some may get properly stuck and drill their way through to the belts. If this happens, the transporter is quick to point it out as a design problem in the tyre. But a couple of minutes taken to clean out the pebbles is too much trouble. These I removed in under a minute with a multi-tool. |
| 22 Here's a nice looking wheel rim. The paint is in good condition, all the wheel nuts are there and there's even a valve cap fitted. Nice work someone! Now, next time you fit such a pretty wheel, try to make sure that you do so in a way which allows access to the inner valve. This is not difficult; you just match up the hand-holes before tightening everything up. |
|
|
|
23 Same vehicle, same pretty wheel rims and a nice set of recently fitted newly retreaded tyres being eaten away by an axle which is way out of alignment. The tyres on the other end are also suffering. Now if you had to ask the owner what his biggest priority in business is, I'd put money on it that he would answer "bottom line" with a suitably satisfied and knowledgeable expression. Well the hot news is that the direction his axle is facing is exactly where his bottom line is going. Into the dirt! |
| 24 Here we go again. Miss-mated hand-holes and no way that the inner wheel pressure is being maintained. |
|
 |
25 This vehicle had come up from Richards Bay. It is likely that the bead damage was recent because this type of damage is known to spread quite quickly and cause rapid tyre failure. The tyre is interesting in that the marking on the sidewall shows how the damage most likely occurred. The tyre was dragged against something like a curb or road edge, weighbridge or loading dock guard or similar. Many would refer to this as driver abuse but usually those people have never driven a truck/trailer combination. There are many areas where it is impossible to turn a rig without doing damage like this to the tyre. Many loading areas are poorly designed and cannot accommodate today's big rigs. So, because problems like this are part and parcel of a truck driver's daily life, you would like to think that the owners, who theoretically should understand their business, would take precautions to keep their vehicles safe and reliable. Well take a look at the next few photos of the same rig.
25a is just a closer view of the damage. |
| 26 See the tyre on the axle just behind the tyre above. This may have happened at the same time but I have the feeling it is older damage.
26a
shows the spare tyre which is actually illegal. So whatever happens, the driver of this rig has no choice. His return journey, probably with a valuable load, is most likely going to include some time at the roadside waiting for the breakdown service to come and change one or more tyres. Is this a professional attitude to the transport business? Would you like to entrust your load to this operator? I certainly wouldn't. |
 |
| 28 As
explained previously and in the last Brake and Tyre Watch, tyres
with different circumferential dimensions need to rotate at different
speeds and if you bolt them together, they cannot do so. The result of
this practice is that the smaller of the two tyres (which needs to rotate
faster than the bigger one), will wear off rapidly and irregularly while
scrubbing rubber off in an attempt to rotate at a speed too slow for it.
Mismatching dual tyres like this is so common it is hard to believe. Just
about every day on the road one can see trucks and trailers with tyres
mismatched in size or pattern or both. The results start showing very
quickly and yet no-one learns from their mistakes (or should that be
mismatching). Why? It is so easy to see, and so easy to understand, and so
easy to fix, and so expensive if you don’t. Why do transport operators
continue fitting the wrong tyres together? |
|
|
|
29 The hole in the middle of this photo is the hand-hole of a well maintained and in fact, quite new outer wheel rim. The little straight thing seen looking through the hole is a reasonably new valve extension fitted to the inner wheel. All good and well one would say, here is an operator who has got it all right. Except that while the valve extension is bent down and jammed between the two wheels, it is not accessible for use. This can happen quite easily when fitting the wheel but it should be corrected before the wheels are torqued up - and certainly before the truck leaves the yard. This is the sort of small thing which shows a 'don't care' attitude in the industry and a general lack of discipline in the maintenance of a fleet. |
30 Now here we have a situation which I love to discuss, a controversial issue which people insist on disputing. Notice the difference in each dish of the two wheels fitted. Now it is generally agreed that steel bent at differing angles will react differently when subjected to the same stresses. Bends and curves in steel cause strong and weak points and when designing certain components, strength is derived from curving or bending the steel plate in a certain way or at a certain point. These are facts known to most people and are accepted and believed in all matters, except when fitting two truck wheels together. Then these facts are forgotten, disputed and generally ignored. Let's go into this one a bit more. Both these wheel rims are designed to do the same job, and both will do it equally well. The problem comes about in service, because although they can withstand the same stresses, they react to these stresses differently because of the differences in dish designs. Bolt either of these two rims to one of exactly the same design, and they will work together in unison. As they are here, the flexing and stresses are not working together and in fact, influence each other to their detriment. Over the years, I have seen wheels fitted like this crack in various areas and almost without exception, you will find after a while that irregular wear will start on both tyres. This is a mismatched rim assembly. The transport operator has rims of both types, as will be seen later. Why not just match up the same rims as a course of normal events. I mean if you're making a sandwich and there are two loaves of bread, one brown and one white, who would in the normal course of events take a slice from each loaf before you slap your cheese and tomato on, or would you match up the slices from one loaf? Once again, I give up!
|
|
|
|
31 At the last Brake and Tyre Watch held in Middelburg, I was concerned about the number of tyres found which were recently retreaded and the casings were in such poor condition that they should never have even been taken in for inspection to be retreaded, let alone ending up with a new tread. When writing the comment for those photos, I mentioned that it was probable that some unethical retreader in the area was responsible, not really believing I would see the problem generally. Well I am now concerned that standards in the retread industry may be dropping, because we found quite a number during the Centurion Watch as well. They were not as ridiculously bad as the Middelburg ones, but I still find it disconcerting. The tyre shown here is fitted to a vehicle which does appear to work in areas with harsh underfoot conditions and because of this, it was impossible to judge how old the retread was. Unusually, there was no indication of when it was retreaded. I say unusual because it is common practice for the retreader to put a mark on the tyre indicating the date of retreading. This also assists in showing how many times the casing has been retreaded. This tyre was not marked at all - and nor were the others we found in similar condition. It was obvious though, that the casing was way beyond it's best for retreading date, even before it was retreaded. If this is a trend that is starting, we need to know about it now and the retread industry should take steps to stop the few who are dropping the standards.
|
| 32 Same vehicle, worse casing, but still a lot of tread life. This is not a safe tyre and casing failure is imminent. This retreader needs to be closed down. |
|
|
|
33 While not illegal, fitting retreads on the steer axle is poor practice and should be illegal. One must always remember that even the best retread on a very good casing is still a recycled product. The strength of the unit is in the casing and the casing will already have covered many thousands of kilometres carrying loads all over the continent. No matter how well the casing is inspected, there is always the chance of some weak area between components caused by some incident in its previous life. The finest retreader with the strictest inspection controls cannot see between the components. I believe in retreading programs in the transport industry and generally I have faith in the retreading industry, but I don't believe in taking chances with safety. The chances of casing failure with a used casing are naturally higher than with a tyre in its first life. So don't take chances. Fit new tyres on the steer axle and retreads further back on the rig. |
| 34 This tyre is smooth, therefore it is also illegal. It is also fitted to the same rig which has the retreads on the steer axle. The following photos, up to number 49c, are dedicated to the immense stupidity of the owner of this rig and to his unbelievable arrogance in thinking he has the right to play with people's lives every time he allows this piece of junk out of his gate and onto public roads. The life of his driver and the countless lives on the roads - pedestrians and motorists - are in danger because of one person not giving a damn. I find this very hard to take. Please take special notice of the following photos, and judge for yourselves, particularly those of you running and owning transport operations, if you believe that this moron should be allowed to operate. |
|
|
|
35
Luckily this...I don't really know what to call it so let's go with 'attempt at welding' - is only holding the mudguard bracket on. It still won't last though and when it falls off on the highway - God forbid that this rig ever gets on a highway - it can still do a lot of damage and could even kill should it go through a windscreen. |
| 36 Worn torque rod bushes, damaged rocker arm, excessive spring pack movement... |
|
|
|
37 Mismatched tyres, in poor condition, fitted to bent and buckled rims... |
| 38 Broken mudguard throwing pieces off as far as it goes, disintegrated rocker arm bush, and torque rod bush... |
|
|
|
39 Cracked chassis, what can I say about the wear at the spring pack??? |
| 40 Broken mudguard missing, retread coming off... |
|
|
|
41 Another disintegrating torque rod bush... |
| 42 More broken mudguards, but they're trying to keep this one going awhile... |
|
|
|
43 The best tyres on the whole rig, but not for long with more destroyed bushes... |
| 44 Nasty casing with irregular tread wear, and the only decent piece if visibility tape on the rig... |
|
|
|
45 More chassis cracks... |
| 46 More broken mudguards, missing mud flaps and a totally illegal wheel track. This trailer was meant to run single wheels but who cares? Lets go duals, they're only sticking out a little bit... |
|
|
|
47 Cracked and rusted axle, bent mudguard bracket...and how far do those dual wheels stick out? |
| 48 One hundred and seventy millimetres, that's how far out they are... |
|
 |
49 Wheel studs too short, 170 coats of hand applied paint...and
49a - all the wheel studs are too short...and
49b - see, absolutely every wheel stud too short and the only valve extension, on all the wheels, is chaffing though on the edge of a hand-hole because the bracket is loose...and 49c - the loadbed is cracked, the tyre has a great big repair busy failing and guess what - a broken mudguard! Over and above all this, the brakes weren't working, the cab was falling apart, the crane was leaking hydraulic fluid like I've seldom seen anywhere and...I can't go on, but believe me when I say this was one of the worst cases of recklessness I've ever seen. The purpose of the whole exercise, why we were there, was to highlight safety. We did not expect to find the one vehicle, possibly in the country, which so perfectly epitomises the very opposite of safety. Maybe it was sent. Road users, beware, we have maniacs in our midst. |
| 50 What's that split-pin achieving? The bolt is doing a good job of increasing the diameter of the hole anyway. The reason for the photo though is this: notice the small shiny spot on the spring blade? It indicates some movement, but most people would not believe that this was responsible for the irregular wear starting to show on the tyre. Please believe me when I say that any movement, in any part of the suspension, changes the original geometry, and will affect tyre wear. In this particular case, this wasn't the only cause, but was certainly an influence.
50a on the same trailer shows a cracked and repaired part of the chassis, and
50b shows another cracked and repaired area on the chassis, very close to the previous one. Both were cracking further beyond the weld.
50c shows another, more seriously, cracked and repaired area on the chassis, and the repair is failing badly, as cheap and nasty repairs are want to do. And again, taking the brunt of the flexing and twisting occurring throughout this scrap trailer, are the tyres. No tyre on this trailer was wearing normally. Trying to keep this thing on the road is a very expensive exercise. The cost in tyres alone, over a period, would probably pay for a new trailer. |
 |
 |
51 This one had me chuckling. This photo and
51a show the tyres fitted to the right side of one trailer. I'm a bit confused as to the operator's understanding of "tyre matching" but his attempt did amuse me. I'm not going to explain again the consequences of fitting two tyres of different overall diameters on a dual fitment. We've done this and I think everyone understands. Now this operator took things to extremes with the differing diameters to start with as you can see, but then he fits tyres of equally differing diameters to the rear axle as well, but in opposite positions. Can this really be his attempt at equalling out a miss-match? I can't believe it! Anyway there we have it. Four tyres which could have been perfectly matched, getting ruined through miss-matching!! Notice how the smaller tyre on each axle has worn far faster than its bigger mate. At the risk of repeating myself ... I give up. |
| 52 Another casing which should never have been retreaded but the tread life remaining suggests that the retread is reasonably recent. This has really become a concern now. |
|
 |
53 Here we have a tyre with obvious signs that it has been run flat, driven totally deflated. And it is quite a new tyre. Once a tyre has run-flat damage, it must be removed from service. This tyre is scrap because, even though there is quite a lot of tread life remaining, it is unsafe. |
| 54 Another example of miss-mated rims. Read caption to photo 30. |
|
|
|
55 Miss-mated rims again, and a damaged and totally useless valve extension. |
| 56 Miss-mated rims again - and this time the valve extension isn't totally useless ... yet! It will be by the time the truck gets home though because it is chaffing through on the rim flange edge. |
|
|
|
57 I have mentioned a number of times how important it is to fit good quality steel valve caps to all wheels. It is also a good idea to carry a few spares but as innovative as this may be, I can't recommend it as a good place to keep a steel valve cap. Apart from being particularly harsh on the cap itself, there is the chance of it drilling into the tyre. Nice to see that there are steel valve caps in at least one operator's fleet though. |
58 Tyre wear on this trailer was strange to say the least. No tyre was exceptionally bad but every one showed signs of more than one wear problem and obviously this would also mean accelerated wear rate. Once we inspected the trailer, the reasons for the tyre wear became more obvious. This rig also ran on 285/65R19.5 tyres but typical of many trailer designs using this size tyre, there was no clear reason for the choice. The original thinking behind the use of these small diameter tyres was to give the trailer designer - and operator - the option of running a lower trailer design which would reduce frontal area and centre of gravity at the same time, with obvious benefits of reduced wind resistance and increased stability, among others. Here at home in S.A., for some reason very few vehicles actually take advantage of this theory and for some reason, normal height remains but the small tyres are still used. In some cases I have seen the plan Africanised by running a low ride chassis while still keeping to the legal maximum height, thereby increasing volume significantly without consideration to load sway and other flaws in the thinking. However, I digress, and need to get back to the tyre problems. Let's just say that this trailer was running the small wheels on a normal height chassis, negating any advantage the small wheels may have, and in fact, this was adding to the tyre wear. Bad idea number one! Then there was the fact that the trailer was in a state of collapse and the repairs done to keep it on the road left a lot to be desired. Spacers fitted to suspension components were badly fitted and then welded in place for some reason, presumably to prevent them moving. What effect this welding had on the bushes behind the welds, I shudder to think. Rubber doesn't react well to that sort of heat at such close quarters. So...bad idea number two.
|
|
|
|
59 Then on the same trailer, someone decided to disconnect the ABS on the brakes. Now I'm open to correction here, that loose wire could be an electronic brake force equaliser too, but I think it is the ABS. Either way, bad idea number three. |
| 60 Bad idea number four, same trailer! Can you believe the spare wheel bracket these guys have designed? Neither nut is going to hold on for too long because they are the wrong size, even the one with the washer. So, easy fix...use wire. Can't find some strong enough? Just wrap more around then. Pretty isn't it? |
|
|
|
61 Here again we have a casing which is in shocking condition but is still in service. This tyre should have been scrapped a long time ago. The other, and even more concerning factor, is that this casing has been retreaded and still has a little more than half the tread life remaining. This again indicates that the tyre was retreaded long after the casing was well beyond a standard which would be considered fit for retreading. It appears as if this is a far bigger problem than I would have believed. The possibility is still there that only one retreader is responsible since the majority of the tyres lack the usual markings. Of all the tyres seen, only three carried the usual markings. I do believe though that this is a practice which needs investigation urgently. It cannot be allowed to carry on, it is a huge safety concern, and again, I find it extremely hard to accept that someone is making money out of a product which is putting lives at risk. This, to me, points to very low form of humanity.
|
| 62 More of the same... |
|
|
|
63 And still more............These are not all on one vehicle. So, as I said, the situation is far worse than I anticipated. I would really like comment from the retreading industry regarding this. |
| 64 Have a good look at the tyre on the rear axle on the outer rear. Notice how the tread is indicating a lateral drag from the right of the vehicle and how the ribs are feathering. All the tyres on this axle are indicating the same kind of wear but diminishing in severity across the axle. This is actually showing us that the axle is out of alignment - or has been in the past - and recently corrected. The alignment of this axle is causing a steering effect at the rear of the vehicle, and all the tyres are showing the effects. Those on the axle are reacting directly to the axle angle, and the others on the trailer are showing the effects of fighting the steering action. |
|
|
|
65 This is just to show the correct length of wheel studs. Compare these with those shown earlier. |
| 66 This is a nice example of how not to do things and, the results thereof. All tyres on this vehicle were showing irregular wear of different types and stages of severity. There were enough reasons for the strange wear, the most obvious in this photo being the miss-mating of the rims. Look at the rims carefully. Miss-mating is occurring on both axles, in opposite positions. This was the same on all axles, and on both sides. It is only one of the concerns; alignment, worn bushes, and irregular brake forces being some of the others. Look closely and you will see that all the elements are there to use the rims correctly and mate them up properly. They would be different over the bogey but the individual axles would be perfectly matched. Just too much bother maybe, or to be fair, it may be ignorance. As I mentioned earlier, people tend to balk at the logic regarding this rim phenomenon. |
|
|
|
67 Another valve taking strain. Jammed as it is against the brake drum, it is definitely getting exposed to too much heat so the valve core is losing tension (this valve was already leaking slightly, and will get worse), and because there is no steel valve cap fitted, the tyre is deflating. If a steel cap had been fitted, it would hold this tyre at the correct pressure even if you removed the core completely. The tyre was reasonably new, and about R2.00 spent on a valve cap would have saved it. As things were, that tyre had about two days to go before it was damaged beyond all repair. |
| 68 Here we go again, one smooth tyre fitted with one with plenty of life. Do you think it was fitted like this at the yard? Well it may have been but according to all the indications, these tyres were fitted at the same time and I believe they were fitted together when they were both newly recapped. So what caused the one to wear so much faster than the other? Well, the rims were fitted in a way that made it impossible to inflate the inner tyre. So we get back to the rotational dimensions being different because the inner is running at a lower pressure than the outer. |
|
|
|
69 This is a novel way to replace a fuel cap but not a very effective one. It also begs the question why would one not replace the cap with the real thing? And I'm sure you are asking "why is he getting into this now, he's the tyre guy not the diesel one?" The problem is that this novel fuel cap is busy causing havoc with the two tyres fitted to the right rear of this vehicle. They obviously hadn't got the plastic to seal properly because the tyres were starting to show signs of diesel contamination. Most probably they are getting sprayed when the tank is properly full and the vehicle takes a left turn. Diesel impregnates the rubber and basically turns it into moosh. So I am still worried about the tyres, see! |
| 70 Have a good look at two points in this photo; one being the inner shoulder wear on both tyres, but especially the one on the truck's right, your left in the photo. Two is the camber of both front wheels, a little on the positive side I'd say.......by about two miles. Then consider how much the toe must be out, really out (toe-out), not just wrong, to allow that sort of wear on the inner shoulder. |
|
|
|
71 This is the way to go. All the right stuff is on this dual assembly, new tyres, new valves, new steel valve caps, new valve extension and new valve extension bracket. So why, I ask with a tear in my eye, is the bracket so far from the extension? Remember that old radio add "makes you think, doesn't it?" Boggled my mind I'll tell you that. |
| 72 Mismatched ODs again. |
|
|
|
73 And again.............. |
| 74 Just the safety warriors..... or should that be worriers? |
|
|
|
75 That black stripe around the inner sidewall is telling us something. It's saying, "something is hurting me......HELP". |
| 76 Ahh yes, there we are, a bit close to that bracket. Another two days travelling should see the body ply cords exposed, and then..........BANG!! |
|
|
|
77 OK! The bent landing legs really won't do anything to the tyres. But the cracks in the chassis will, and even more probable is the cause of the cracks, overloading, flexing - whatever - will definitely have had a very direct effect on the tyres. Now that the cracks have developed, the flexing will be more and will change in character as the cracks grow, having an ever greater detrimental effect on the tyres. |
| 78 And grow they definitely are... |
|
|
|
79 Even the tail board is cracked. The rigidity originally designed into this trailer has been altered through all the cracks, at least in the chassis itself, which will have a direct effect on the tyres. The tail board won't have a direct effect on the tyres but remains a safety concern since, if they leave it as it is, or even fix it as badly as they have other cracks, the thing stands a good chance of actually falling off. That could put a nightmarish slant on your trip down the highway if you're behind this trailer at the time, I'd imagine. |
80 This alloy wheel has been butchered beyond belief. Take a close look at the wheel nuts. They are the wrong type for the hole design - and also the wrong size. But the operator came up with a cunning plan, or so he thought. They just kept turning the nuts in until they ground themselves into the alloy. Maybe they thought the hexagon shape would stop the nuts loosening. Well, I've got some news for them - and it's all bad. The nuts are still grinding the alloy away and it won't be too long and this wheel and its mate will climb off and pass the truck. I find it difficult to believe that people take chances like this with safety. A small application of general logic should tell anyone that this is a bad idea. This was on a break-down truck by the way. Imagine the exciting experience ahead of this driver when he has recovered some fully loaded link from an accident, down the way a bit, and the left rear wheels say good-bye! Imagine the chaos! And the carnage!
|
|
|
|
81 Look closely - unbelievable isn't it? And one studs already broken as well! |
|
|
| 81 Have good look at this truck and pick out the most obvious faults. I have a concern that most of you won't even pick anything up because you are seeing the same thing every day on many trucks, from many different companies. We discussed the tyres on this truck earlier. They were all bad. What I'm looking at now is a safety issue that concerns me and although I should only be talking tyres, this is of interest to all road users, and therefore as a road user, I have every right to question the practice. And so should all of you out there. Take numbers and report every truck you see like this one with a load which is not strapped down or netted, or in some way made safe. The scrap metal guys are the most guilty of all with unsafe loads. But here we have an operator who not only considers it OK to not strap his bricks down but probably tells himself that the weight will keep each pallet down. Again, I've got bad news for him. And if that isn't bad enough, they throw up a loose spare wheel and tyre on top of the loose load and then they don't secure that either! People, finally I give up! |
IN PARTNERSHIP WITH THE
FOLLOWING COMPANIES
|
