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Old 12-08-2016, 11:25 PM   #8 (permalink)
lgirard
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Quote:
Originally Posted by BGTV8 View Post
Dude, check your maths ....... 265/35R19 is ~ 668mm in diameter and 285/35R19 is ~ 682 mm in diameter.

Difference is outside tolerance (just) and is enough to upset the ABS calibration.

The ABS brake controller is monitoring the number of rotations front and rear to detect a locked (or about to lock) wheel and because ofn the sizes, it is getting confused as it will not tolerate more than ~3% difference in diameter and rotation speed. This is NOT in the ECU, it is in the ABS controller.

I run 265/35R18 front and back on 10" wide rims for track duty - for DD use I have a set of 245/45R18 and 275/40R18.

Your tyre size choice is the problem and a fix in the ABS controller is probably beyond anyone other that the ABS system OEM.

That I understand ... I originally started with that setup I it became clear to me that the problem was with diameter diference. where I am confused though, is when I brought back my 245-40-19 while keeping my 285-35-19. Diameter difference is now within 1%. and I am still experiencing ABS over reaction. is there some other criterias like rear tires diameter must be lower or equal than front tires !

thanks for you help
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