Run Flat Tyre Wear

[mgooda]

Somebody please tell me, 9500 miles with both front tyres needing replacing is unacceptable??
Pirelli Run Flat, 19", c250 W205 AMG Line.
I got 20k out of the 18"s on my W204 Sport Plus.

Both are completely worn on the outside edges and need replacing. Am gobsmacked!

Similar experiences anyone??

 

[Meldrew2]

Tracking correct? A FWD carshould do more miles!

 

[mgooda]

Tracking correct? A FWD carshould do more miles!

Tracking, alignment is all fine. Pressures regularly checked. Rears were the first to go on my W204. That had standard Continental Compact 5's fitted.
These are Pirelli P Zero run flats and I'm told they are a softer tyre but I'm no expert.

 

[grober]

Could be the toe -in is set incorrectly or it may be due to a more fundamental suspension geometry effect which may be more marked on a wider tyre setup. Mercedes are known to run higher than usual caster angles to improve their high speed stability and this is known to cause tyre shoulder wear due to camber change with steering angle when cornering.e.g. While the outer wheel in the turn gains negative camber[good] the inner wheel gains positive camber [bad] -- explained here.
Using Caster to Properly Align Vehicles

 

[gIzzE]

This was a major issue for BMW when they started using runflats some 12 years ago, it took them almost 10 years to get the geometry right to stop edge wear. Saw so many tyres being dumped as the edges were down to the cords while the middle 80% still had 7mm remaining.

I would consider dumping the runflats completely as they also ruin the ride of the car.

 

[mgooda]

This was a major issue for BMW when they started using runflats some 12 years ago, it took them almost 10 years to get the geometry right to stop edge wear. Saw so many tyres being dumped as the edges were down to the cords while the middle 80% still had 7mm remaining. I would consider dumping the runflats completely as they also ruin the ride of the car.

Thinking that but the rears are fine, and would guess you can't mix run flat rear and std front.
MB suggested a Bridgestone replacement as harder wearing, I'd like a contribution as shot tyres in less than 10k miles is not good.

 

[JDL60]

Never had run flats ( glad to say) but old logic used to say that if the outers of the tyres are worn and the rest ok, then the tyre was under inflated - is that less true of run flats?

 

[Meldrew2]

Never had run flats ( glad to say) but old logic used to say that if the outers of the tyres are worn and the rest ok, then the tyre was under inflated - is that less true of run flats?

OP says outer edge worn - if the tyre was under-inflated would not both edges be worn?

 

[mgooda]

OP says outer edge worn - if the tyre was under-inflated would not both edges be worn?

Never been under inflated, if anything slightly over on occasion.

 

[JDL60]

Never been under inflated, if anything slightly over on occasion.

sorry, I did misread and thought it was outer edges not edge. In that case it's (as mentioned already) a camber issue. I had that (not on run flats to be fair) and it was camber

 

[JDL60]

OP says outer edge worn - if the tyre was under-inflated would not both edges be worn?

you are right

 

[gIzzE]

No, don't mix run flats front an rear, in fact on a rwd car don't mix treads either, can often be fine but can make it very, very twitchy.
I say ditch the lot and put some thing like a Dunlop EfficientGrip on all round instead.

Sell the rears on eBay if it helps, but get them ditched they are ****e.


I took a new C205 estate out and thought it rode terribly, never even considered it may have been shod with run flats, but it had all the traits of them, so thinking back I bet it did have them fitted. Stopped me buying one.

 

[gIzzE]

Oh, and Bridgestone is without doubt the worse runflat I have experienced, RE050 I think they were, but god they go slated, like riding on concrete tyres.

 

[robfloorlayer]

Somebody please tell me, 9500 miles with both front tyres needing replacing is unacceptable??
Pirelli Run Flat, 19", c250 W205 AMG Line.
I got 20k out of the 18"s on my W204 Sport Plus.

Both are completely worn on the outside edges and need replacing. Am gobsmacked!

Similar experiences anyone??

your lucky i got 6700k on 1st tyres and 6300k on 2nd tyres no tread left
front on 2nd set
back going on to 3rd set now
13000k
c250 amg line 245/40/18
its good on fuel thou lol

 

[Scooby_Doo]

My previous car Passat CC 170 Diesel came new with Continental self sealing tyres, fronts totally worn at about 7000 miles. Fitted normal Continentals as replacements, 1st pair about 8500 ,second set about the same , when I sold it with 26000 on the clock it had it's 4th set of fronts on. 18" wheels .

 

[Rory]

Good grief - some of those mileages are horrible.

None of this is encouraging me to buy a newer car. I only changed my fronts as they got to 6 yrs old - they still had 4mm at 45000 miles.

 

[190]

Even old Mercs have a fair amount of castor and therefore camber under lock.

I would think the implications for tyre wear are made worse for wider tyres, for tyres with low profiles and for tyres with stiff side walls (run flats) as they can't flex to keep the enough tread on the road surface. If this is the case I doubt higher than spec tyre pressures would help as that just makes the tyre even stiffer.