fixed one problem, created another

[60ratrod]

ok so my replacement hubs fixed my road noise hum, but now my abs is either over active when slowing down below 20mph or my abs light comes on and i stop normally, but i think my abs goes inactive. and this all started when i replaced the driver's hub. both hubs came with new speed sensors. so what i did was i swapped in the old speed sensor after looking at the reluctor ring inside to make sure there wasn't any issues with the reluctor ring. but i did notice a couple of things. one, there was alot of grease in the old driver's hub, or at least on the teeth of the ring and there was only a small amount on the new one, could this be an issue? second i noticed that there was what looked like a couple of shims under the new sensor. when i swapped the sensor out with the old one, i reinstalled the shims. could this also be an issue? i think my first step here is going to be removing the shims, after measuring the distance from the mounting surface to the top of the teeth on the reluctor ring. and there was no change when i swapped out the new sensor with the old sensor

[beingblueeyes]

yea i would try to re-move the shim and see if it makes contact, if no contact is found try it like that and recheck the weather tight connection.

[MidwestSS]

did you plug in the sensor? should have had a new electrical connector to install with the new hub(s)

[Frenchy]

GM hubs or aftermarket?

[oleshifty]

I think any brand BUT timken will cause this problem. You can try to remove your factory sensors from old hubs and install in new hub (actually fixed the problem on our tahoe), if not, pull the ABS fuse, break the bulb in dash, and live on (what I did with my silverado)...or toss the new parts and get some OEM replacements.

[60ratrod]

well last nite i hopped on the gm global that my dad gave me access to and came across a bulletin about too much space between the sensor and the reluctor ring that's caused by corrosion. and since these are gap sensitive the shims are what is probably causing my issues. now i gotta wait til the weather clears to take a look. i hate doing work in the rain

[60ratrod]

i fixed the low speed abs actuation. turns out that the new sensors on the new hubs are longer that the old original sensors. hence the need for the shims. i measured both sensors and the old one measured out at 18.32 mm and the new sensors measured out at 18.99mm. the shims were anywhere from .15mm all the way to .40mm. so what i ended up doing is removing all the shims from the driver's hub since i reused the old sensor and used one shim that measured out at .20 since i used the new sensor. now my abs light is off and the abs is no longer over active!