lauer87

Hey guys, I'm thinking about putting Pilot Sport A/S on the C55. Only problem is that they only come in 40+ profile sizes. If i run the 245/40/18's in the rear, the total diameter from tread to tread will be 25.7". The stock rears (245/35/18) come out to be 24.75". You guys running 265/30/19's diameter is 25.26". I think they probably will fit, but i thought I'd ask to see if anyone knows if the aprox 1/2" will make a difference?
Thanks in advance

SilverBulletAMG

Yes, a 255 will fit on an 8.5" rear rim with no rubbing.

FrankW

245/40/18 is 3.7% too big. it's recommanded you stay within 3%.

check http://www.1010tires.com/TireSizeCal...?action=submit you can calculate what'll fit better and what will not.

SilverBulletAMG

I dunno...not sure what difference 4% makes with actual fitting, but I know guys with C55s running a 255 wide 18" tire with an 8.5" rim. Other than throwing the speedo off a little, what's the issue?
Also, according to that link it says the stock tire size is a 225/45/18 for an '06 C55. Isn't that just the front rim size and not the rear? That's what it defaulted too at least. I'm not sure what you put initially to compare it too.

FrankW

oversizing by that much might also throw off the ESP because front and rear are spinning at different rate.

you can run 255 on 8.5 without any problem.

stock size for C55 is 225/40/18 and 245/35/18. Before the C55 came out and the updated AMG site if you checked the optional wheels for C32 the recommand tire size was always 225/40/18 and 255/35/18. I don't know why they changed it, but they did change it to the new spec. I would still run 255/35/18 just because it gives you little more traction and better lip protection on the 18x9 and 18x9.5 most people run.

if you want to compare all the tires just use the 225/40/18 as a base and input all the rest in there.

FrankW

btw, on our car we could actually run 235/40/18 and 265/35/18 and still have smaller diameter than the 235/35/19 and 265/30/19 which all of us run.

lauer87

Thanks for all the timely replys, my dilemma is that no matter whose All Season High Performance i look at (Conti,Mich, Etc.) the smallest profile they come in is 40+. I know the Mich Pilot A/S are great tires in terms of overall performance grip coupled with tread life, but not knowing if they will fit i think I'm going to order the Conti ExtremeContact because i can get them through my friend for about $430 for a set, versus aprox $1100 for the Pilot A/S. I'm going to order them in the next day or so, I will keep you guys posted.

AWDman

225/40 -18 and 255/35-18 all seasons also made in 245/40-18 for all around.

the overall increase in diameter with 245/40 should not affect you. you may get interference with inside front fenderwell plastic at max lock.

http://www.discounttiredirect.com/di...r=40&tc=HANHZ3

http://www.discounttiredirect.com/di...r=40&tc=MMIHZJ

if you are not dealing with a huge amount of snow then maybe the staggered allseason fitment would work.

dlourens

I have vredenstein sessanta 255/40/18 on the rears and with speedbumps or heavy dips or with loaded car, they do touching. I only realise after ordering the tyres and delivery that they are not 255/35/18. They do grip like hell.

Lenin

I hope you pay more attention to your driving than when buying tires or replying to posts that are 7 years old. But welcome to the forum anyway.

Gramma_Benz

dlourens

No need to be an ******* about it. The fact that tyre size of 255/40/18 does touch only under heavy load is still valid and useful - especially after 7 years, new tyres for these cars come out all the time...

Gramma_Benz

No worries, you're contributing useful information.

Welcome!