Clicking/Grinding/Pulsing brakes

[MacGyverDB]

Hello all
My parents (Mostly my Mother) are at their wits end concerning their 1997 Grand Cherokee's grinding/clicking/pulsing brake problem
They have done the following:
pads replaced
rotors replaced
calipers replaced
brake hoses replaced
glides/slides replaced
tie rod in middle replaced
new hubs both sides
abs brake module replaced

ANYONE got a clue on what in the world is happening to this?
My Mom did note that at one point the ABS light came on..and while it was on the problem went away. Are they looking at bad ABS Sensors?
It grinds, clicks and the brakes pulse like it's fighting back the driver.
There isn't much left to replace on the front end.

[JDPascal]

Welcome to AF!

Wow!!

If all that work was done to fix this problem, thats a lot of bux and not have it fixed yet......

With you description of the problem going away when the ABS lite was on, I would agree that it is likely an ABS system related malfunction. When the lite is on, the ABS is disabled in a "failsafe" mode.

Is the "feel" of the problem in the brake pedal and transfered to your foot? Have you (they) ever driven the jeep on ice and applied the brakes? Is the feel similar?

First thing to check with an ABS problem is the tire make, model, size and pressure. They should be identical on all four corners. The tread wear should also be as close as possible.

Check to see if the ABS set any codes when the lite came on.

Might it be that the actual problem has changed slightly since the work was started and we are now dealing with something different but similar?? With the range of adjectives that you use to describe the symptoms, that seems a possibility to me. Hard to know at this distance. Not doubting you here, just asking to give a new perspective.

A sensor could have been damaged after the original problem was fixed or when some of the parts were replaced. The sensor should be check-able by someone who knows how to use a multimeter or with a scope.

JD

[dksob81]

Originally Posted by JDPascal

Welcome to AF!

Wow!!

If all that work was done to fix this problem, thats a lot of bux and not have it fixed yet......

With you description of the problem going away when the ABS lite was on, I would agree that it is likely an ABS system related malfunction. When the lite is on, the ABS is disabled in a "failsafe" mode.

Is the "feel" of the problem in the brake pedal and transfered to your foot? Have you (they) ever driven the jeep on ice and applied the brakes? Is the feel similar?

First thing to check with an ABS problem is the tire make, model, size and pressure. They should be identical on all four corners. The tread wear should also be as close as possible.

Check to see if the ABS set any codes when the lite came on.

Might it be that the actual problem has changed slightly since the work was started and we are now dealing with something different but similar?? With the range of adjectives that you use to describe the symptoms, that seems a possibility to me. Hard to know at this distance. Not doubting you here, just asking to give a new perspective.

A sensor could have been damaged after the original problem was fixed or when some of the parts were replaced. The sensor should be check-able by someone who knows how to use a multimeter or with a scope.

JD

Also, check the RING TONE GEAR for damage or excessive build up (dirt, grease, etc.), I just got over a similar problem in my 94, not quite as bad tho but on some ocassions it would start pulsating on it's own without even applying the brakes, altho mine was not as severe, it is very similar. I had a slightly damaged ring gear (3 teeth were a lil smashed together) and caused my ABS to go crazy when slowing down around 8 MPH. I replaced the AXLE SHAFT and it took care of the problem.

[JDPascal]

Good point dk

JD

[MacGyverDB]

Originally Posted by dksob81

Also, check the RING TONE GEAR for damage or excessive build up (dirt, grease, etc.), I just got over a similar problem in my 94, not quite as bad tho but on some ocassions it would start pulsating on it's own without even applying the brakes, altho mine was not as severe, it is very similar. I had a slightly damaged ring gear (3 teeth were a lil smashed together) and caused my ABS to go crazy when slowing down around 8 MPH. I replaced the AXLE SHAFT and it took care of the problem.

Hey there...Sorry it took so long to get back and reply. Life in corporate America...more overtime than ya could shake a stick at...

Anywho...from what my parents eventually found out...I think they said it was a speed sensor on one of the axels was not working right. Either it would be totally on or totally off. Once changed...no problem.
Evidently these sensors feed into the ABS.

Thanks for the other advice though I'm going to pass it along to them. It's getting worked on again right now...but not for anything in specific..repair work from an accident. Everyone's ok, my Mom was in her first accident that she was behind the wheel of...they need to rebuild from the headlight back on the driver's side.

Have a MERRY CHRISTMAS !!!