I have Michelin Pilot XGT V4s on my 260E.

Size: 215/60V15 on stock 15-hole rims.
The car's standard tires are 195/65V15.

The manual says to inflate to 29 psi front and 35 psi rear (plus 6psi if you are running over 100mph.)

Because my tires are bigger, should I be following those guidelines? Right now I am at 35 psi front and 41 psi rear. I get the feeling I can add another 5 psi or so. Can I?

Eric Silver

Your increase in pressure will certainly affect handling -- usually improving it, up to a point when the pressure is excessive. But your question started off implying that you just wanted to match the criteria used by MB in deciding on your "owner's manual pressures".
Here's what to do. You'll need to go to a tire store and ask for their copy of "Tire Guide" -- it's a trade publication that lists, among other things, load ratings for all tire sizes at all tire pressures.
Look up your OEM tire size, and then look up the load rating at your front and rear tires' pressures.
Next, look up your new (bigger) tire's size, and look at the table for the same front and rear load ratings -- then see the pressure indicated that provides those load ratings.
This will not improve your handling markedly, but will help to maintain the MB-intended ride and handling balance (understeer/oversteer). And more important, it will serve as a better starting point from which to experiment with higher pressure to enhance your car's performance.
Hope this helped.

Just be aware that plus-6 for 100+ means like if you run 100+ for hours at a time, not brief periods. 35/41 is WAAAAAAY too high. Keep it at 33/35 MAX. Your tire is going to blow up. Not to mention you have less rubber on the road, making it handle worse. Only tire that feels really good at high pressure is the Michelin Pilot Sport.

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1988 Mercedes-Benz 260E (W124)
Arctic White/Grey
Debadged
Euro Headlights
Clear Turn Signals and 1994/1995 Taillights
16" x 7J 8-hole
Michelin Pilot HX MXM 205/55WR16

1997 Mercedes-Benz E420 (W210)
Pearl Black/Ash
Debadged
Michelin Pilot XGT Z4 P225/55ZR16

1997 Mercedes-Benz C280 (W202)
Polar White/Parchment
Michelin Pilot SX-GT 205/60VR15

this is a very good question and I hope everybody reads this.

Although many people upgrade their vehicles wheel and tires to larger sizes they often inflate their tire incorrectly. The air inside your tire is what supports your vehicle and offers the needed stability to the tire for your specific car. The tires main reponsibility other than traction is to contain the air that is supporting your car.
Always follow the recommended air pressure for your specific application and do not worry about a differnt size tire because, it is the air that supports your car.

Thanks, Luke

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Luke Pavlick
Performance Specialist (ASE Certified Master Tech)
Please, call me to place orders (800-428-8355 ext. 362)
or mention my name for on-line orders
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to visit Tire Rack web site)

I'm running 215/60/15 Goodyear eagle responedge's on my 95 E320 wagon. I guess I have been running them too high (approx. 38psi all around)..... I'm at 15k miles on these guys and they are getting uncomfortably close to the tread bars. too bad. I rather liked these tires. Kauffman tire guy almost didn't rotate and balance them for me.

I'm prolly gonna go back to 205/60/15 and maybe get those RE960 pole positions. My dad is running RE960's (albeit 195 series) on his '95 E420 and they are pretty sweet.

unless you guys have size and or tire recommendations.


BTW reviving an 8 year old thread rocks

Thats probably too high. If its too high the tires will wear out in the center.

I agree with Luke.

I would start with the recommended pressure and only deviate a little if use showed there was a problem that could be affected by air pressure I would adjust it a bit. I would not expect to need to.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.