2001996c4

Hello all, had some alignment issues last summer. Changed the tire size on a "tuned" suspension. Since tire change car has driven poorly to say the least. Aligned twice with no improvement. I did replace Michelin ps2 with pilot super sports. It seems the biggest problem was changing from 275 40 18's to 275 35 18's thought going back closer to stock was a good idea. Only recently by dropping tire pressure from 38 f 42 r to 29 f and 32 r has the car driven closer to "normal" I'm a little concerned about driving at these pressures as they seem a little low, thoughts???

Thank you!.

Hurdigurdiman

What is the correct tire pressures for this car? What is the correct suspension for this car? What is the correct wheel alignment for this car under normal driving conditions? Questions answered. That's OIMHO.

Rob996

Tire pressure for your car is 36f and 44r. I enjoyed the ride with the psi at 32f and 38r. Having the correct tire size is very important beyond ride comfort as the awd system needs the right height ratio in the tires.

GL

Dstutler

At 36f and 44r my car has a tendency to dance a little at higher speeds therefore I've backed off to 32f and 36r and it settles right in. I have 235x40x18 on the front and 285x30x18 on the rear and they are Michelin Sport A/S.

Byprodriver

Staying close to stock tire size is a good idea. OEM psi specs are for oem sizes. Dropping 10psi in each tire is a big difference & MPSS tires have a relatively soft sidewall so they seem to need 2-3 extra psi to feel right. I assume you dropped psi in steps not all at once. The issue is load capacity since it is the air pressure in the tire that supports the car so to answer your question you must find out the load capacity of your tire size with that air psi & see if it is adequate to support the weight of your car + occupants & etc. I assume you have the proper diameter F & R tires for AWD, but I believe you need to add psi, it's always better to have too much vs too little psi.