Vincenza V

I am new to Jeep and 4x4's. I have a 99' 4.0 Cherokee that has 136K miles. When coming to a stop while breaking-I notice a faint "whump-whump" noise. That's as best as I can describe it. To me it solds like a bad bearing. Is that a common thing to go at that mileage? JC Whitney has the whole shebang for a decent price. I don't want to replace a part if it's not the problem.

I had a Lexus GS400 that had a few thousand dollar put into it to chase down a notorious vibration these cars a plagued with and nothing helped. The Lexus dealer started guess at the problem after nothing worked (I did the whole front suspension work myself, but used them as a consultant only) and I sold the car. I love this Jeep and want to methodically tracy down the problem. I haven't put the truck on jackstands to check the bearing, but if it passes the normal test for bearings (where you grab the tires and push-pull from the 9-3 and 12-6 positions) does that mean it's NOT the bearing? Thanks for your help!

http://www.jcwhitney.com/wheel-hub-a...DetailTabPanel

94JeepCherokeeMan

There could be something going on with the rear brakes. When you have it jacked up, make sure you closely inspect the brake drum and shoes for any oddities, like glazed surfaces or bad spots on the pads. Hell, take it to Les Schwab and the brake check is free.

That's what I would check first.


Rob

tannerp89

sounds like your rear drums are out of round...

VTJeep

if things move arond when stopping or taking off, they tend to move with an accompanying clunk, pop, or possibly a whump type noise... things like u joints tend to be the culprit most of the time. everytime i take off in the am and i get to the end of my drive and stop, my breaks clunk and it feels like something is shifting around. im pretty sure my u joints are going (again...) this time i plan on shelling out a little more for good ones- spicer make good joints. get under the jeep and grab the drive shafts (DS) and try to twist it back and forth. there should be no play in them. my rear is solid for now, but i know im gonna be on front DS number 2 real soon... its iddy too, cause you gotta replace the whole thing... last time it cost 90 bucks for one... the other u joints are in your hub assembly. jack the jeep up enough to get a tire off the ground, grab said tire top and bottom and see if you can get tip. any movement other than it spinning around means youll prob be replacing u joints soon... idk, its pretty common w/ jeeps and pretty simple to fix... good luck

revision: i hate not reading the orriginal post well enough... you said it was a whumping when ON the breaks also you mentioned testing the wheel joints already... sorry for telling you to do something you clerarly are aware of... i guess i neeed more coffee... my next thought is yea, pull the drums apart and check em out...

Vincenza V

Guys-thank you so much for your words of wisdom. I will put her up on stands this weekend and check. I've rebuilt disc brakes, but have never had any experience with shoes. It seem WAY more complicated. Is there a way to see if the drum is out of round? I like the idea for checking the drive shaft VT. Are you saying there should be now play whatsoever when twisting in fore and aft (the direction it normally turns) or in and out. Where your drive shafts the worn part or the hub/bearing assembly? I am new to 4x4 and it's a learning experience for me. Thanks!

Vincenza V

All the talk about the brakes, had me thinking. Don't know if it's related but here it is. The brake feel relatively strong to me (I haven't ever driven one of these to compare it to, but compared to other vehicles, seems strong) and sometimes (more often than not) when I press on the brake pedal, the very first 10-20% of it's movement-it "falls". What I mean is it ever so slightly drops, but not enough that most people would notice. I am very in tune with my vehicles so I notice everything and it drives me crazy. I don't know if the lines need to be bleed again or if that issue is contribting to the noise. Just a thought.

johnydoe

i had the same problem...well still do...

baught my jeep, 98 cherokee, the back brakes were not working so i didnt hear the noise, then i got my rear brakes completely re-done, then every time i step lightly when coming to a stop it would make this "tok-tok-tok" noise, almost like for every rotation of the wheel there was one "tok"....

so i wen to the back of my truck and shook the truck violently with my hands...and i could hear a "tok tok tok" and from what i could tell it was comming from the hub...


i asked around on another forum, and what i was told is either a bearing or the c-clips and diff pin that are worn out of finished

2 weeks ago i had a brake line replaced and with my mechanic i asked him to test it out, so we grabbed the axle and moved it side to side and there was no loose, so berings are fine, but then we noticed we were able to move the axle in and out of the shaft like 1/4", both sides......so we came to the conclusion that its most likely the c-clips and the differential pin that is worn or finished

95Cherokee

I have more strange noises than I can shake a stick at, I've given up on most of them.

Also, my brakes make a "shhhhh" sound when applying the pedal, I don't think Cherokees were meant to be noise free.

j-rod

id start with inspecting brakes...then u joints.

The JRod

Probably Going to be warped Rotors on the front! Very slightly warped rotors cause noise rather than vibrations. It is Possible that it could be the Rears however.... to test to see if its the rears, You get to just above the speed this issue normally occurs, And SLOWLY engage your Hand brake. If no noise or Vibrations its not your rears! Normally it is the fronts as around 70+% of stopping power is the front brake on Vehicles with drums on rear! This is very common when using "Cheap" rotors! GL & let us know what you Find! Bet it's the fronts!

Trickynick89

Wheel bearing gone bad or low fuid in your diff maybe

Firestorm500

You brake booster is bad. Bad diaphragm.

CherokeeCountry

I have this same thing. Booster hard to change???

Firestorm500

Mechanics generally charge 1.0-1.5 hrs to do it.

94JeepCherokeeMan

Or you could get an fsm and do it yourself...