help needed : ABS goes nuts !

[Crizz]

Today I wondered running down from a hill. At a speed of r.a. 30 mph in the cirves suddenly tghe ABS started to work, though I didn´t hit the brakes ! Only when running iddle downhill, and at spped higher than 20 mph only. No warning lights, no MIL, no message in the console - nothing.

Have no clue what went wrong, does anybody have an advise ? It scared me a lot, was the first time it happened.

 

[Crizz]

Seems i fixed it. Don´t know exactly what happened, but it seems it was caused by my tires. In Feb. I had a flat and needed to change both rear tires because the org. Ford-Michelin isn´t available in GE. So I run A/T´s on the front axle and Wintertires on the rear.

When I changed the wheels with the ´99´s-ones, I swapped the front- and reartires as I mounted the original wheels again.

Mayber it was caused by the different grip of the tires that the ABS-function was so sensible, now that I swapped the wheels from front to rear again the prob seems to be gone. Crazy.

 

[cwescapexlt4x4]

Were they different sizes by chance, thus creating a "speed difference" between the front and rear wheels?

 

[Crizz]

The nominal tire size is the same : 235 / 65 R 18 . But as far as I remember is the tire-profile of A/T´s deeper than thus of "Streettires". This can result a different wheelspeed between front & rear axle, indeed. I only wonder why it does only effect when running the "little" tires on the front axle, and the difference cannot be a lot. But it can be the result of different tire size plus different grip.

No matter how, it really seemed to be the cause of this effect, drove around 100 mls today w/o any probs.