Front tyre wear, outside edge

[wheels-inmotion]

Any chance of a write up on this, maybe a pic or two as I'm very interested to see how it goes.

I realise WIM is a commercial business so may not want any trade secrets or working prctices to be revealed.

We don't expose any data unless the owner permits it.... The owner is welcome to disclose any data without our consent.

Any track specific data belongs to the owner who is unlikely to expose it due to the possible advantage to the competitors.

Our sponsored race cars we retain all data and rights.

 

[merc07]

I guess Tony could do a write up on his findings. I can give him the 'Chassis alignment test sheet' from Mercedes and a run down on how the car pulls - I mean drives.

From what I understand only the Rear axle Toe and Front axle Setback / Toe measurements have changed since Mercedes messed with it.

I could post a couple of pics of my michelin slicks if you like. - Well the outside of the left front is slick anyhow.

Cheers
Adam

Edit - I don't have competitors, can't remember the last time I saw a C220 CDI estate race at Castle Coombe !!

 

[wheels-inmotion]

I guess Tony could do a write up on his findings. I can give him the 'Chassis alignment test sheet' from Mercedes and a run down on how the car pulls - I mean drives.

From what I understand only the Rear axle Toe and Front axle Setback / Toe measurements have changed since Mercedes messed with it.

I could post a couple of pics of my michelin slicks if you like. - Well the outside of the left front is slick anyhow.

Cheers
Adam

I cannot comment on the calibration unless it's approved by the owner, nor can i take images or offer results, albeit good or bad.

 

[merc07]

Thats my front tyres after 21091 miles, looking at them from the front of the car.

The left pic (drivers) was about 5mm inside, 2mm outside.
The right pic (passenger) was about 4mm inside, 0mm outside.

The cars 'Toe', passenger side was adusted by Mercedes about a year ago to try and stop it pulling hard to the left - The adjustment didn't work and Tony from WIM reckons that is what has caused the severe wear.

As well as resetting the 'Toe' he also fitted an adjuster bolt to the drivers side and altered the caster - making it slightly less in relation to the left side.

New Michelin Primacy HP's were also fitted.

Before I took the car to WIM, if you held the steering wheel straight, then let it go it would always jump to the left the same amount - 12 o'clock to 10 o'clock then sort of roll on it's self and keep turning even more. I would actually have to hang onto the wheel and hold it quite firmly to the right to make sure I kept straight. - Not good on a motorway journey.

The drive home - 130 miles was alot easier. The car will still pull to the left but I think that is the normal camber sensitive pull - more of a bad wander. The actual steering wheel doesn't turn itself to the left like before and I don't have to hold pressure to the right to stay straight.

I don't know if the worn tyres caused it to pull worse, The Mercedes adjustment to the Toe or the fact that the Caster needed to be adjusted.

One thing I might need to reset is the steering wheel as it is now slightly to the right when driving straight. Was there something I read somewhere about turning it lock to lock a few times or was that for something else / another vehicle ?

All in all, nice friendly guys to deal with, thanks Tony

Cheers
Adam

PS 52mpg round trip on the clock - probably 50mpg in real world - Just 1 accident with air ambulance on the way up the and 1 accident with a complete closure on the way back - not bad for the M4 on a Friday !!

 

[whitenemesis]

Lock to lock thing is to reset the steering angle sensor

 

[merc07]

What does that do ? - Is that what I was after ?

Cheers
Adam

 

[whitenemesis]

No, it doesn't do anything for the steering wheel mechanical angle.

It's all about ESP and pitch and yaw. Software stuff

 

[Dieselman]

Any figures from the alignment rig?
I remember seeing your n/s tyre at jay's do and it was pretty scrubbed, although the overall readings don't indicate heavy wear.

It will be interesting to see how it all goes from now, although the pulling sounds a lot better.

 

[Rory]

Thats my front tyres after 21091 miles, looking at them from the front of the car.

The left pic (drivers) was about 5mm inside, 2mm outside.
The right pic (passenger) was about 4mm inside, 0mm outside.

.....

Before I took the car to WIM, if you held the steering wheel straight, then let it go it would always jump to the left the same amount - 12 o'clock to 10 o'clock then sort of roll on it's self and keep turning even more. I would actually have to hang onto the wheel and hold it quite firmly to the right to make sure I kept straight. - Not good on a motorway journey.

The fronts on my late 04 C270 estate have worn *exactly* the same as yours. Mine are a little more worn overall - the tread is worn smooth on the passenger side outside edge - but the tyres (Bridgestone Turanza ER30's) have done 35k.

My car doesn't "jump" left as you describe, but it does roll with increasing force so, just like yours, has to be held right.

The other issue I have is the car feels like it's squirming, and never feels "planted" on the road. I actually don't really like driving it.

I bought the car at 5mths/6K miles and it drifted left then (I knew to look for it and the salesman said they all do it - it ran straight when driven down the crown of a road). I've never had the alignment done and doubt it had been done before I got the car.

After my last trip to the dealer, where they said mine is actually better than most, I brought the car home and swapped the front wheels over. MB recommend swapping diagonally to test but my car has staggered wheels so can't do that). Since the fronts where swopped it runs almost perfectly straight! I assume this is the worn nearside edge that is now on the offside edge pulling the car right.


To be honest, I'm almost scared to get the alignment done, particularly by someone some distance away, as I've heard horror stories of C Class's being messed up. I also don't really want to pay, when I've already got a ServicePlus contract running and they ought to cover it (but the dealer won't even request it). Mine is annoying, but not horrendous. It'll need new tyres soon so I'll see how it goes then.

 

[xpc316e]

I have always set the front wheel alignment of my cars by examining the way the tyres are wearing, and combining it with the feel of the steering. Once I am satisfied with the way the steering feels, I find that the tyres wear evenly. I have bought a few cars over the years which were really awful to drive, an MGB and an NG kit car stand out in my memory; after a few weeks of experimentation and adjustment, they were restored to being a joy to drive with light, informative steering despite the amount of castor the MGB has. I say ignore so-called factory setting and set toe in/toe out by feel.

 

[merc07]

To be honest I don't trust the main dealers, they actually broke 4 separate parts of my car, on 4 separate occasions and left me to find out for myself !.

But maybe they are right when they say all W203's pull to the left.

Any how, attached are the alignment details from WIM. As you can see, I had a bad Toe !. and the right Castor was dropped. - It shows the same before and after but apparantly they are both the after readings ?

As I said in the previous post the car still pulls left quite hard, but the difference is that I don't have to hold pressure on the steering to make it go straight on. I think this may have alot to do with having the new tyres fitted though. It feels alot better to drive. I'll have a better idea after a week of driving.

In short I guess the wear issue may have been sorted (toe adjustment) but the general W203 pulling is still there.

I also found this useful info:

http://www.continentalimports.com/ser_ic4232.html

The bolt shown in figure 1 is the same used by WIM but they only fitted 1 of them - to the drivers side. According to WIM they dont offer much adjustment. Maybe it needs one on both sides with opposite adjustments. ?

Cheers
Adam

 

[Dieselman]

It shows the same before and after but apparantly they are both the after readings ?

I don't follow you. Do you mean the actual readings are the After adjustment ones.?

 

[Dieselman]

If I read that correctly the car has slight right rear steer and less caster onthe o/s front wheel. This should make it more prone to pulling right I think.

Which way is it pulling?

 

[merc07]

I think what Tony said was for the Castor readings only, they represent the Actual/After readings. They were measured first but not printed out. The car was put back on the ramp later when the adjuster arrived and only measured again once it had been fitted.

Maybe Tony can clarify this. - He might have the original data ?

If this helps, the values I have from the Mercedes alignment 12 months ago were :

Caster Left : +10:39
Caster Right: +10:48

Again I'm really not sure this caster adjustment made much if any difference at all.
No adjustment was made to the rear.
It pulls to the left.
Tony set the caster this way to compensate for that - I guess make it pull right to get it to go staright on ?

Cheers
Adam

 

[Dieselman]

You will get an idea of how the tyres are going to wear if you draw a chalk line across the tread in a cross. The more level this wears indicates that things are good.

 

[wheels-inmotion]

I think what Tony said was for the Castor readings only, they represent the Actual/After readings. They were measured first but not printed out. The car was put back on the ramp later when the adjuster arrived and only measured again once it had been fitted.

Maybe Tony can clarify this. - He might have the original data ?

If this helps, the values I have from the Mercedes alignment 12 months ago were :

Caster Left : +10:39
Caster Right: +10:48

Again I'm really not sure this caster adjustment made much if any difference at all.
No adjustment was made to the rear.
It pulls to the left.
Tony set the caster this way to compensate for that - I guess make it pull right to get it to go staright on ?

Cheers
Adam

The reason the before and after figures are the same is that we had already measured the car and established what was needed i:e the castor bolt.

The car was removed from the rig so that other cars could be calibrated whilst we got the "correct bolt"..... Then we installed the corrective bolt then measured the chassis again hence the same before and after figures.

To belay a pull/ drift camber and or castor stagger is often used but since the calibration positions on the MB is so small i cannot afford to violate this without generating another level of tyre wear.

It's kind of robbing Peter to pay Paul.

 

[Dieselman]

As a matter of interest how do you go about installing the caster bolt with the suspension built up.?

I know how I do it but you may have a better method.

Given the after figures why do you think there is still some drift.? To me it looks as if it should drift to the right now, not left.

 

[wheels-inmotion]

As a matter of interest how do you go about installing the caster bolt with the suspension built up.?

I know how I do it but you may have a better method.

Given the after figures why do you think there is still some drift.? To me it looks as if it should drift to the right now, not left.

I think the method would be global.... Wheels raised, calculate the bolts position, install, pull tie-rod to gain purchase and tighten.

I feel the reason for the drift is the camber positions... If we had a gradual type of adjuster i would stagger the camber but we don't.

The bolt offers a "matter-of-fact" +- 30' either direction on either wheel, will in this case generate tyre wear.

Peter+Paul....

On some MB we do stagger the tyre pressure or if the car is having tyres we stagger the pneumatic drift.. This is a powerful long term solution.

 

[Dieselman]

I meant how do you actually get the bolt in given the joint is still under considerable pressure from the road spring.
My local centre refused to fit them so I did it myself. I just followed the old bolt out with a long extension bar, then pushed the new one in using the bar to align the holes.

I still don't understand why it's still drifting left given the after readings. Seems a bit odd.

 

[wheels-inmotion]

I meant how do you actually get the bolt in given the joint is still under considerable pressure from the road spring.
My local centre refused to fit them so I did it myself. I just followed the old bolt out with a long extension bar, then pushed the new one in using the bar to align the holes.

I still don't understand why it's still drifting left given the after readings. Seems a bit odd.

The castor bolt is not under tension "happy days".... The camber bolt is tricky but not scary so i don't understand the local centres attitude?

The pull??

The reason for the pull is the road crown, so why the MB i hear you say?

On most cars the crown is absorbed by the tyres compliance and the suspension, technically both are able to adapt to the crowns attitude.

The MB's coils and pneumatic compliance denies this adoption and is literally steered by the crown.

Geometric stagger would belay this but it moves the calibration into the realm of tyre wear.

I can make the MB do anything handling wise but it's never without consequence if we move away from the OEM settings...

In truth i feel MB have dealt the owners in the UK a bum hand, it would be interesting to know what "official" distance is recognized in the UK for the MB's "eventual drift?"

Eventual drift?
Most manufacturers give a distance that the car must maintain before deviating from the intended line.

The manufacturers guidelines determine a complaint or not.... Is anyone aware of the official limits for the MB?