Front wheel sensors

[GARY BRUNGARD]

Is there a good description or manual to help in repair the front wheel abs sensors.I have to disconect the abs fuse because when using the brakes with the fuse in sometimes I have absolutly have no brakes the pedal is hard as a rock to push down.

[tempfixit]

What year, 2 or 4 wheel drive?

Go to this site I think it will be helpful to you:
http://www.autozone.com/az/cds/en_us...rInfoPages.htm

[wafrederick]

What year and is it a 4x4?There was a recall which does not fix it at all.The fix for the recall was to clean the wheel speed sensors and GM does not cover the wheel bearing under the recall.The only real fix is to replace the wheel bearings instead of replacing the speed sensors

[GARY BRUNGARD]

I should have said what I have it is a 98 k1500 and wafrederick when I bought the truck of a 2 year lease I had this probleme and brought it to the dealer and that is what they did they cleaned it and it worked for about a year and then it came back since then I drive it with the fuse pulled. Other than that it is a great truck.

[wafrederick]

I hear about this a lot.My father's 2002 GMC Dually went through this and it was gone after replacing the left front wheelbearing.I replace the front wheelbearings a lot on GM fullsize trucks and the problem is fixed with the customer very happy.

[GARY BRUNGARD]

So just by changing the front wheel bearings it should clear up the the problem, and what is making it bad in the first place?

[tempfixit]

I do not understand how a bad wheel bearing will cause a hard brake pedal.
wafredrick could you please explain how the bad bearings cause a hard pedal.

thanks for input

[maxwedge]

The wheel bearing failure can cause excess clearance in the sensor ring so the abs does not see a signal hence a possible abs issue, the more common problem of premature abs activation is usually caused by the mounting flange on the knuckle rusting and affecting the sensor. None of these issues can cause a hard pedal, if anything a really worn bearing that will move around, causes a low pedal.

[GARY BRUNGARD]

Well I have to tell you I was surprised as hell when I could not push the brake pedal down fast enough before almost hitting a car at a stop light!!!!!!

[tempfixit]

I am at no means underestimating anyones knowledge or experience on this issue. I recommend having the abs system checked with a ABS capable scanning tool rather than throwing parts at it.

Would the abs module cause a hard pedal??

[j cAT]

Originally Posted by tempfixit

I am at no means underestimating anyones knowledge or experience on this issue. I recommend having the abs system checked with a ABS capable scanning tool rather than throwing parts at it.

Would the abs module cause a hard pedal??

I would check vacuum at brake booster engine running.... does it hold vacuum at booster with engine then shut down.....this would cause a hard brake pedal..... recall was for 99 on up for abs front wheel sensors.....could be abs unit causing loss of braking and by removal of fuse this is now inoperative...and braking is improved....

I never heard of abs causing hard pedal, but if its pulsing that would be abs......,and if it pulses when braking at low speeds this would be abs wheel sensors/or conn./wires etc...

[GARY BRUNGARD]

When I did bring it back to the dealer when I first bought it about 3 times they said finally they replaced the bearings and there to this day is no abs codes that come up unless I pull the fuse even when the fuse is in and I can bearly push down the brake pedal I still get no codes or the abs light.It seems very strange how bearings can have this probleme with the sensors I do recall hearing it is in the shape of a star pattern (the sensor).

[j cAT]

Originally Posted by GARY BRUNGARD

When I did bring it back to the dealer when I first bought it about 3 times they said finally they replaced the bearings and there to this day is no abs codes that come up unless I pull the fuse even when the fuse is in and I can bearly push down the brake pedal I still get no codes or the abs light.It seems very strange how bearings can have this probleme with the sensors I do recall hearing it is in the shape of a star pattern (the sensor).

you have a brake booster that is leaking or a bad vacuum line to booster.... this will cause hard pedal..... no abs codes,,,,this is more normal as abs causing hard pedal is not a failure that i have seen....

[GARY BRUNGARD]

Would you agree that even if I take the abs fuse out I would notice a falling brake pedal that would not hold say at a stop light eventually the pedal would drop all the way down if it were a vacuume leak or a bad booster. When the fuse is out my brakes are perfect minus the abs feature.

[j cAT]

Originally Posted by GARY BRUNGARD

Would you agree that even if I take the abs fuse out I would notice a falling brake pedal that would not hold say at a stop light eventually the pedal would drop all the way down if it were a vacuume leak or a bad booster. When the fuse is out my brakes are perfect minus the abs feature.

No I don't agree!

a soft /dropping brake pedal means a loss of brake fluid/defective master cylinder...

a hard brake pedal is loss of vacuum to brake booster/or brake booster has a leak.........

I still can't understand how the abs can cause a hard brake pedal.........in your vehicle......perhaps someone can explain how this can occur......