SL/R129: R129 Tire Sizing
Thread Starter
Newbie
Joined: Aug 2013
Posts: 14
Likes: 0
1991 Mercedes 300 SL
R129 Tire Sizing
Hi, I have a 1991 Mercedes 300SL with AMG 3pc Aero rims (like these https://www.benzworld.org/threads/am...-sale.1589303/). On the rear are 2 year old runflat 245/45 ZR17 95Y M+S Tubeless Radial X DOT 4M 9D 005X Michelin Pilot Sport A/S Plus (runflats since these aluminum rims lose air especially when sitting over the winter but I have since been told employing runflat protection would ruin this type of three piece rim). Currently on the front are 235/45/17's which need to be replaced. I've been told stock tire size for SL's up up to 1998 is either 16 inch, 225/55/16 on all 4 corners or 18 inch staggered 245/40/18 on the front and 275/35/18 on the rear (and "height is important so that your sensors aren’t confused"). I don't really know tires and definitely want to keep the rims (if not the near rears as well) so any recommendations/guidance would be appreciated
Super Member
Joined: Aug 2019
Posts: 702
Likes: 207
From: Lutz, FL
1997 MB SL600
So replace the run flats with the same size of another tire.
The sizes you state preserve the integrity of the standard tires sizes which work with the car's sensors.
If you currently don't have any problems with ABS or cruise, don't change the sizes.
The sizes you state preserve the integrity of the standard tires sizes which work with the car's sensors.
If you currently don't have any problems with ABS or cruise, don't change the sizes.
Thread Starter
Newbie
Joined: Aug 2013
Posts: 14
Likes: 0
1991 Mercedes 300 SL
Fwiw occassionally both the ABS and Brake warning lights come on and stay on while driving -- though the car does not go into limp mode or anything and the lights turn off if the car is turned off and on. I have kinda suspected the worn 235s on front vs. new 245's on back might be the cause (long story) but will post more details after tire replacement in case it can help future readers.
Also this https://www.alloywheelsdirect.net/in.../mercedes-benz was posted at a different forum and recommends 245' all around (though when I follow it's links for the rims to https://www.alloywheelsdirect.net/me..._3pc_wheel_510 seems to suggest "front & rear: 235/45R17".
Also this https://www.alloywheelsdirect.net/in.../mercedes-benz was posted at a different forum and recommends 245' all around (though when I follow it's links for the rims to https://www.alloywheelsdirect.net/me..._3pc_wheel_510 seems to suggest "front & rear: 235/45R17".
