2012 merc amg

I'm thinking about making this change when I replace the tires, the 40 profile which the car calls for I believe makes the rims more susceptible to bend over sharp bumps and I've experience a lot of this in the past. My S class which uses 245-45-19 has never had a bent rim, on my 2019 E450 bent 4 rims and counting. Probably going with non run flat should help out with this issue too, currently have michelin Primacy Run flats on the car. I know the speedometer will be off slightly but thats ok.

Povitica3

I am planning exactly that once my current RF stock tires either gets busted or worn out. Shouldn’t be too far from now cos I have about 14,500 miles on the car. Will be replacing with non-RF Michelin Pilot Sport tires. Besides giving the rim more cushion against potholes, a 45mm tall tire fills the wheel well better and gives the car a better look.

2012 merc amg

yes exactly. It should fit just fine. No idea why mb went with the 40s with the 45s the tire is a little less wide too but that extra height could be crucial in protecting the rims from potholes. One not even too big pothole is all it takes to bend front and rear rims at one shot with the current tire profile setup and the run flats. Poor design. Not enough rubber between the rim and the road with the 40 series tires.

The G Man

The 45 on the tire size is not a measurement in mm, it is the aspect ratio of the width of the tire compared to the sidewall. If the tire is 245mm wide, the 45 ratio represents 45% of 245mm which is 110 mm. The sidewall of that tire is 110 mm.

2012 merc amg

So probably gain roughly 10mm sidewall with going from 240 to 245. Should be an improvement. Would just like to hear from someone who runs the 245s on their cars vs the 240s. I couldn’t have been the only one getting bent rims and looking for a solution. 240 is just too low a tire profile for this car as far as I’m concerned strange mb put this size tire on this car. Not like it’s a sports car or anything.

JakeW213

its to get the circumfence that the car is born with - across all rim sizes.


I run these on a W213 220d
summer:
Front 245/35-20
Rear: 275/30-20

winter:
Front: 255/35-20
Rear: 255/35-20

the winter setup is slightly taller as you can expect… but ride wise its about the same

I have no issues, I suspect that bent rims has more to do with road surface than anything else.

The G Man

Going from a 40 to 45 ratio on a 245mm wide tire should make the sidewall 6mm thicker, not a lot of difference. Changing to non-runflat should make a bigger difference. Runflat’s stiff sidewall transfer the force to the rims on a pothole. A smaller rim would make a bigger difference in sidewall height. Do you already have forged wheels?

2012 merc amg

I’d bent two of the stock wheels which are in boxes in my garage and put on mandrus wheels a couple of years ago. Back then the roads were a lot worse than they are now in Rhode Island and New York. I’ve mostly had the car in Florida since then where the roads are smooth and no issues but two of the mandrus wheels are a little out of round from back then. I just live with a little bit of steering wheel shake and can feel a small vibration in the rear. Gotta find a place that can fix the wheels for when I do the new tires. I figure do it all at once since the tires will be off then anyhow.