Uneven tyre wear MK2 Ambulance

[Gunslinger]

huh ..... nah, if you have uneven amount of turns on one end compared to the other, all that will happen is that you'll not be working from the middle of the travel for the rack/box, and thus will decrease your turning ability one way and hit the end stops the other way before the box/rack reaches full travel.

That Ackerman angle thing you are talking about is determined by the angle of the steering arms connected to the hubs if i am not mistaken, sure it will knacker your tyres, because the difference in angle between the wheels/tyres will be wrong from the start and then as you turn that error will increase, but it wont have caused the one side only wear that he was experiencing to start with

[FredTransit]

I think it's tracking too. We have to replace many a front tyre early on one of the lutons because of it, and I can't find anywhere local (including where we buy tyres on account) to adjust it.

[Gunslinger]

i would also be wary of these "all singing and dancing" laser alignment things. especially if the wheel contraptions fix around the tyres ..... far to much room for error, should always go to the rim or hub, otherwise the snot nosed kiddie trying to set it up will always get 2 different readings from 2 separate attempts on the same vehicle

[chrisvmax]

Hi, and thanks for all the replies, sorry my initial description wasn't comprehensive enough.

Both of the front tyres wear too fast on the outer edges. They both wear at the same rate. At the moment both front tyres have worn all the tread from the outer edges and there is still 5-6mm of tread left on the inner edge.
The steering feels fine when driving, it does not pull to one side or the other, it's not notchy or anything, it is heavy when the van is not moving but that is to be expected (it's a heavy van)


The van does feel really smooth to drive, but it is a bit wasteful as it wears front tyres too quickly.

I'll try to take some photos of tyre wear and view of wheel from front of van tonight and see if I can post them on here.

Regards,
Chris

[Gunslinger]

ok thats easier, if its scrubbing the outer edges of both evenly then it narrows it down quite nicely,

1) tracking .... toeing in too much
or
2) camber angle wrong

so to narrow it down further, we come to your description of how it feels, if its smooth when turning or going lock to lock, and doesnt suddenly get easier, and doest feel like your driving on the edge of always wanting to turn one way or the other (too much toe in would create a small "window" for going straight, it would always be trying to push one way or the other, making it edgy in a straight line) then i would start to look at the camber ....

exaggerated, but here is what i mean ..... your wheels might be doing this \ ------ / (thats viewed from the front, and is the same affect you will see when lowering the front end down after being jacked up) this will cause the outer edges to wear, and you wont notice anything major on the steering side of it, especially if it has always done it as you will have nothing to compare it too.

What causes it ? ..... worn kingpins are a possibility, although i would be inclined to think this might be a weight transfer issue because as i said earlier ambulances are lighter on the back, so if you load them up the front becomes light ..... this is my bet for your problem

How to fix it, tough one, there are a number of thoughts on this,

1) Get the front end stuff checked, shocks and kingpins, make sure spring shackles arent seized (but i doubt its that) also, does it have antiroll bars fitted ? ..... not sure if these can affect the camber if something is worn
2) change the rear suspension, swap the shocks and springs for the ones from a van that are not as soft and designed to carry more weight, thus transfering some of the weight back to the front
3) make sure the front end springs etc havent been uprated, making it sit higher
4) add wheel spacers to the front or fit slightly larger tyres (although i would not recommend this as a fix, it might be an interesting test, the theory is that a wider footprint will reduce the positive camber and make it sit squarer on the tyres)


if your not convinced about the camber thing (because it looks ok) then i guess the place to start with would be the tracking, you could always try toeing it out a little more than it is currently and see if that helps without affecting the steering feel


Good luck

[AndyG]

Hi, and thanks for all the replies, sorry my initial description wasn't comprehensive enough.

Both of the front tyres wear too fast on the outer edges. They both wear at the same rate. At the moment both front tyres have worn all the tread from the outer edges and there is still 5-6mm of tread left on the inner edge.
The steering feels fine when driving, it does not pull to one side or the other, it's not notchy or anything, it is heavy when the van is not moving but that is to be expected (it's a heavy van)


The van does feel really smooth to drive, but it is a bit wasteful as it wears front tyres too quickly.

I'll try to take some photos of tyre wear and view of wheel from front of van tonight and see if I can post them on here.

Regards,
Chris

Sounds to me like this vehicle hasn't been tracked correctly ie; too much tow in
Maybe they can't undo the lock nuts and simply say it's fine

[AndyG]

i would also be wary of these "all singing and dancing" laser alignment things. especially if the wheel contraptions fix around the tyres ..... far to much room for error, should always go to the rim or hub, otherwise the snot nosed kiddie trying to set it up will always get 2 different readings from 2 separate attempts on the same vehicle

I fully agree How can you possibly even think your gonna get a decent reading from the rubber

[Valsheda]

I had problems with the passenger side tyre, they had to heat up the bolts to adjust it, now running dead center and has been fine since, if you have no joy you could get a full geometry test done, bot sure how much that costs though.

[MrMPuk]

Mine was £25 at Protyre.

[FredTransit]

LWB TW Mk2s have deeply dished wheels, though. That's what put people off putting them on the standard tracking rig, so I am told.

[MrMPuk]

That just sounds like another one of the stories they use to get out of having to do the tracking.

[AndyG]

hhmmm interesting ....... regular full lock U turns .... how many are we talking about here and could that have been your original problem ? and yes i agree sounds like they toed it out to compensate, its strange that your original problem was wear on the outside, as that kind of negates worn parts causing one side wear only (unless the camber angle is screwed)

Sometimes none other days four plus It all depends.
And yes, I do think this is my problem
I don't think it's cureable unless I stop using full lock (fat chance )

One thing I have noticed If you drive forward on full lock the outer wheel and inner wheel both lean inwards at the bottom and if you reverse they have the oppossite effect and lean/splay outwards towards the bottom. I have found this happens on alot of vehicles. But not on all
Any ideas

[FredTransit]

That just sounds like another one of the stories they use to get out of having to do the tracking.

I have heard that too! I can hardly hold a gun to thier heads though.

[Gunslinger]

we now have 2 problems running in the one thread ... oops, this could get messy.

Firstly .... i forgot to add that there is one other possibility to wear on the outside edges only, and this could also be an issue, but i would have hoped thay would have noticed this at MOT time .... your shocks could be totally screwed, allowing too much body roll, causing incorrect weight transfer side to side and causing the tyre to "roll over" more) thus scrubbing the outsides.

Secondly

One thing I have noticed If you drive forward on full lock the outer wheel and inner wheel both lean inwards at the bottom and if you reverse they have the oppossite effect and lean/splay outwards towards the bottom. I have found this happens on alot of vehicles. But not on all
Any ideas

Thats weird, if something was worn i would have expected the opposite affect, we are talking rear wheel drive here arent we

[AndyG]

:lol: we now have 2 problems running in the one thread ... oops, this could get messy.

One thing I have noticed If you drive forward on full lock the outer wheel and inner wheel both lean inwards at the bottom and if you reverse they have the oppossite effect and lean/splay outwards towards the bottom. I have found this happens on alot of vehicles. But not on all
Any ideas

Thats weird, if something was worn i would have expected the opposite affect, we are talking rear wheel drive here arent we

Well you did ask for it
Rear wheel drive. But this has been obsereved on both

Simply drive forward on full lock 2 or 3 yards/metres get out and have a look, head on, from a distance.
Now reverse and do the same keeping the same lock.
See what I mean