2011 W212 E250 - rear tyres heavy wear in middle?

[Will]

Another small consideration is are you using MO tyres? I’ve had brand new ones and measured the tread depths slightly different across the tyre - I guess they may be slightly shaved/contoured to account for stuff like this? Ie tapered off at the edges slightly for the rear.

 

[derektrotter]

Another small consideration is are you using MO tyres? I’ve had brand new ones and measured the tread depths slightly different across the tyre - I guess they may be slightly shaved/contoured to account for stuff like this? Ie tapered off at the edges slightly for the rear.

Yep current rears are goodyear efficientgrip MO with the centre wear, fronts are contis which have worn fine.

 

[190]

I've had centre wear in the past using recommended pressures. When driving solo I'm currently running 5% below the 3 persons plus some luggage pressure and wear looks even.

Another option is to rotate the tyres although not literally rotate around the car in the old traditional sense. To maintain direction of tyre rotation I swap fronts to rears on the same side. Fronts tend to have more shoulder wear which is the opposite of the rears with centre wear.

 

[400ixl]

To maintain direction of tyre rotation I swap fronts to rears on the same side. Fronts tend to have more shoulder wear which is the opposite of the rears with centre wear.

Being careful the OP does not have staggered rims of course which pretty much rules out any rotation of tyres.

 

[Deleted member 6183]

I had the exact same wear on my last two large MBs.

If wear is important then I can tell you how I sorted it.

The wear that you have indicates over inflated rears and under inflated fronts.

I ran mine with the Psi at the lowest recommended at the rears and the highest recommended on the fronts.

The reason that I wanted to avoid wasteful wear was that I was doing 50k miles a year, mainly motorway, and I ended up seeing 40k on a set of tyres by making the above adjustments.

 

[grober]

It may be that in recent years many manufacturers have upped their recommended tyre pressures beyond what's necessary to decrease rolling resistance/improve emissions. Increasing tyre pressures increases their speed rating/load bearing characteristics and affects cornering slip angles. That's why many cars have higher rear tyre pressures than the fronts to give the car primarily understeering characteristics. Dropping the rears a couple of psi is not a problem but more than that means you should start to drop the fronts roughly the same amount to keep that fore and aft pressure difference or accept the car's handling may change slightly.

 

[markjay]

I get the car through full-geometry alignment as a matter of course whenever I buy a new set of tyres, and regardless of whether the old tyres had any obvious signs of uneven wear.

I get it done at WIM, if no adjustments are needed that they charge very little just for the testing and the printout, and if any adjustment are needed then it's money well-spent.

 

[markjay]

One other things to consider, are these the factory-fitted wheels, and are the tyres the correct/original size?

Using the wrong tyre size for the rim width can also cause this type of wear.

 

[190]

... Increasing tyre pressures increases their speed rating/load bearing characteristics and affects cornering slip angles. That's why many cars have higher rear tyre pressures than the fronts to give the car primarily understeering characteristics. .

This will be it exactly, they are paranoid about avoiding oversteer. Just by looking at tyre deflection you can see there is more weight over the front wheels and yet even the lightly laden recommended pressures are usually higher for the rear than the front. If the pressures were based on capacity to support the weight alone, the rears would be lower pressure than the front. I compromise and run them at the same pressure all round unless very heavily loaded.

 

[markjay]

Increasing tyre pressured also improves the manufacturer's emissions figures for the model.

On my Suzuki, there's the usual tyre pressure range of 33psi to 38psi which is called 'Comfort', and then there's an additional single figure of 41psi called 'Eco'.

I suspect the Eco figure is there just for the emissions testing, but you are not really expected to drive using this pressure in real life...

 

[derektrotter]

Yep its the original wheels and the tyres are Goodyear MO rated at the rear.

I've now gone for 4 Goodyear Efficientgrip XL MO tyres, I'm hoping the XL rating will help, also going to run rears at a slightly reduced PSI as per the useful replies i've had here from other peoples experience

 

[steveq]

Why did you go for XL?
I thought they were for Extra Load and hence would have stiffer sidewalls giving a firmer ride?

 

[Ed65]

Centre wear is a typical wear characteristic of rear low profile tyres, centrifugal force 'throws' the centre of the tyre out, obviously only very slightly and over thousands of miles - but sufficient to cause accelerated wear in this area.

 

[optimusprime]

Mods to rear suspension, ie springs and shocks can make these problems that you have .But as we all agree your over inflated .The pressure given in the hand book is for those tires fitted at the time of the cars manufacture . .As the car gets older and new tires are fitted,, then also the tire pressures do change with them.The tire depot should know the right pressure if you ask them just what pressure you should inflate them with .By the way did you ever say just what pressure you do put in the tires ?