Hi. I have just put a nice new set of wheels on my car. I used to be running standard 17x8 inch GT wheels with 245/45/17's front and 275/40/17's rear. The new wheels are Saleen 18x9's (255/35/18) front and 18x10.5 (295/35/18) rear. Now after driving for 10-15 minutes the ABS check light comes on. The brakes still feel fine and i can't notice any problems. Does anyone have any answers? I read somewhere (i Can't remember where) that maybe, becasue the rolling radius of the rear wheels is a little larger (about an extra 2cm on the diameter), the sensors are picking up the difference in the front - rear wheel speeds and this is setting off the check light....?

I look forward to any suggestions as the brakes are somewhat important to someone like me who likes to drive (cough) quickly!

 

Looks like you already know the answer.....a difference in speed between the wheels and no brakes applied, makes the ABS system wonder and light the ABS indicator. The only problem with that is that the ABS option might no be available when you need it....conventional braking is not affected.
How to compensate for that?...a tuner might do the trick. GL

 

Try this link to a great diagnostic how to.

http://www.veryuseful.com/mustang/te...sDiagInfo.html