michail71

So I have 27K miles right now with original tires up front and probably about 7K on the rear tires. They are all OEM Continentals.

The problem I have is the front tires are cupped on the inside and driving me crazy!!! They still have good tread depth. The rear tires still look new and have no issues.

I would like to get Michelin Pilot Super Sports as my next set but I'm not sure I can wait till the the fronts and rears wear down. How bad would it be to have the Michelin PSS up front with the Continentals in the back? I know it's not recommended to mix speed ratings (Y and H) and the PSS are summer tires and the ContiPro Contacts are all season.

Most discussions I've seen on mixed speed ratings mention stiffer cornering/sidewalls on the higher speed rated tires. And that is with closer matched tires. The OEM are 130 MPH and the Michelins are 186 MPH. So these two are rather far apart.


The other option is to get Continentals up front but then they would still be good by the time the rears needed replacing.

I know the best option is going for all 4 but the rear tires are in such good shape.

Adi-Benz

Well people now know your story. You could attempt to sell the rear ones and see what you could get to buffer the price of new ones.

I'd go all 4 cause mixing is also just...eww. As for the posts below, they are all correct.

Carsy

Michael,

It is unfortunate that you have the impractical & expensive option of different sized tyres front & rear. It is a silly fashion fad . I suggest you look into what is involved in having the same sized tyres fitted all round. You will then be able to rotate front to rear, rear to front to prevent this costly unnecessary occurrence.

Also unless you are a racing driver or drive at the absolute limit of your tyres I suggest it is perfectly OK to have high quality different brands front & rear. I have done so many times because tyres have become unavailable & have not once had anywhere near a bad experience. It is not the perfect solution but your plan is to work in that direction.

Just remember tyre shops are keen to sell you tyres & some others are fixed in their ideas by fashion. Do what is best for your own situation.

Young John.

LCPLPunk

First, I would find out why your front tires are cupping. Is your suspension good? Did you track your tire pressure regularly?

As far as mixing and keeping your stock rears, how often are you going to 100+ and holding it there? I don't think I've seen even 80 yet (live in Hawaii where the highest speed is 60) and I wouldn't worry at all about mixing brands.

C300Sport

I agree with the previous posters:
First, find and repair the cause of your cupping.
Mixing tires front to rear is no problem.
Most would say don't do it from side to side...although unless you are really pushing your car hard or you have markedly different types of tires, it really isn't that bad....I wouldn't do it, but in a pinch...
I moved to a square setup from the factory staggered and am very happy with it. At these car's level of performance, a staggered setup is really more vanity than performance.

michail71

I had three things on my car when I took ownership. The rims on the right were bent. The car needed an alignment and I needed the front wheel bearings repacked.

CarMax took care of the rims and the alignment and Mercedes did the wheel bearings under warranty. Odd part about the alignment and cupping is the alignment on left was off and the damage to the left tire is worse. I would have though the damage to be worse where the bent rims were. The bearings on the left were also off more than they were on the right.

As far as the suspension goes Mercedes disassembled and re torqued the front suspension when they did the bearings.

Even with the rim damage every tech that has worked on the car has been puzzled by even the alignment being off and the bearings.

From the reading I've done I've inferred putting the PSS up front could create a situation similar to having a stiffer sway bar up front. I'm not racing but there is the occasional Florida driver or pedestrian on flocka to dodge.

I think I'll get going on the front tires and then see if I can find a buyer for the rears.

sagar526

There's no issues running different tires. I've been running pilots sports on my front tires and continentals on the rears. Been doing this for the past 20k miles since I go through a rear set in less than a year.

michail71

Thanks, that will be my exact setup come this Monday. How do you like the PSS up front?

Carsy

Nice to see some one on the same page & not a slave to US MB convention.

Adi-Benz

Agreed. It's a good look, but serves worse function wise when it comes to switching ones out and such.

michail71

I can't even tell looks wise. I've seen some BMWs with more extreme differences.

Funny how the tire shops love to point out the staggered setup. I also had a few try to talk me out of the Pilot Super Sports.

I'm not sure what the dealer is pushing but they have the Good/Better/Best tire signs with insane prices. I think on of their "Best" tires costs almost as much as a full set of PSS.

Anyway, I'm excited to be getting the new tires tomorrow. I can't take the cupped tires anymore. But I'm still wondering what caused the cupping. I had a slight alignment issue and bent rims. Both of which have been corrected. Any why would the alignment be off on the opposite side of the bent rims?

Acapulco Bill

Had severely cupped edges, especially the right front, on my OEM Michelin Primacy HPs after 28k miles. Replaced with Hankook Ventus S1nobles (a great choice for the W204 and 3-Series imho), and were aligned by an independent alignment shop that worked on my exotic V12, Audi S5 and M3. A few months later the C300 Sport felt like it was drifting to the right, with the beginning signs of edge cupping again.

Took it back for another alignment , the tech told me: "Yeah these W204 C-Class always pull to the right, the lower right arm has no way to adjust the caster (or toe-in). Some customers have paid $800 to install a new arm end from MB that is adjustable, still this doesn't fix the problem, you'll be wasting your $$$."

He then went on to say that to keep my C300 from pulling to the right, he adjusted the suspension for increased overall toe-in, reset the center, swapped the two front tires (if the C-Sport weren't staggered it would have been front-back) and increased the pressure on the front tires so they ran more on the tread and a bit off the edges. Finally he added that my particular W204 pulls only very, very slightly to the right after alignment, some customer's C Class will practically take a right turn if one takes their hand off the wheel even after alignment.

This info from the senior tech at what is considered SoCal's best alignment service with over 50 years in business. My C300 now drives straight, and I will see if edge cupping begins again, but none I can detect after 7k more miles. Find it surprising that MB would produce a vehicle where the right arm has no separate caster adjustment screw. Just sayin'.

Graphic of tire malady and cause below.

michail71

OMG, the car rides so much smoother now! I hope the cupping doesn't come back.

Perhaps the only complaint I have is I don't quite like the looks of the Michelins as much but you'd have to look really close to tell the difference anyway.

Glyn M Ruck

The pulling with the camber of the road is common. Fit fluted bolts in 3 way bushes & dial in 1 more degree castor (max 2) on the passenger side of the car than drivers side. Typically 10.6 & 9.6 degrees.

psaldanha

Is this why some W204 slide a little in the back, especilly when changing lanes?

Acapulco Bill

Thanks, Glyn, for your excellent answer. Seems that some "engineers" thought they were killing two birds with one stone. IRL however this arrangement is far less robust than conventional configurations and places uneven pressure and eventually premature wear on the rubber bushings. Extreme adjustment would result in an appreciable change in the geometry of the suspension. Is this Mercedes' idea of "The Best Or Nothing"?