abcus Posted May 17, 2012 Share Posted May 17, 2012 I have read a few threads under bearings and differentials but I still have questions. the car: I bought a 1987 gl wagon a year ago. It has 190,000 on it now. I had a new cv joint put on the right front wheel and i installed a new rotor also. It is 4 wheel drive. Symptoms: I have a rasping noise that gets louder when I turn right. When I turn left it goes away unless I only go 2 miles an hour. I took a length of garden hose and put one end above the differential inboard . I heard no noise. Then I hung it out each window near the axle. The left rear axle seemed the loudest. When I backup there is no noise. When I run it on gravel in 4 wheel drive going forward there is no noise. When I jacked it up and held the coil spring I felt vibration when I spun the wheel. That brake drum had a lot of black dust in it. The differential was hot after a 60 mile trip. The driveshaft has 1/4 " play in it. The front and rear bearings do not get hot. The noise stays the same in or out of gear w/ clutch in or out. Noise changes a little with application of foot brake. Hand brake does not change the noise. Questions: 1. Should I change the dif. oil ? 2. Can I use a differential from a 87' gl automatic on my car ? 3. Are there any other ways to isolate the problem ? Quote Link to comment Share on other sites More sharing options...
naru Posted May 17, 2012 Share Posted May 17, 2012 1.Nah 2.Not sure,but,I think they are different ratios.Check the sticker on the cover if it is still there. 3.I would check for play in the LH wheel bearings. Sounds like one of them is loose enough to allow the shoes/pads to contact the drum/rotor when highly loaded in a RH turn. Almost certainly the rear since it has extra brake dust,noise and vibration. As rear bearing repair requires axle removal as a preliminary step,you will be able to rotate the wheel and axle bearings independently before being completely commited to the repair. Quote Link to comment Share on other sites More sharing options...
WoodsWagon Posted May 17, 2012 Share Posted May 17, 2012 Most likely a brake component related noise. Check that the drum isn't rubbing on the brake backing plate because of it being bent or really rusty. Check the bearings and the shoes on the left rear. Highly unlikely to be anything to do with the rear differential and axle shafts, they're pretty much indestructible in stock form. Quote Link to comment Share on other sites More sharing options...
ShawnW Posted May 17, 2012 Share Posted May 17, 2012 Hold the strut spring with one hand and spin the wheel+tire. You can usually feel the grittyness in the wheel with bad wheel bearings. If you don't feel it, drain the differential and look at the fluid color. If it looks old change it and road test. Quote Link to comment Share on other sites More sharing options...
abcus Posted May 23, 2012 Author Share Posted May 23, 2012 thanks for the help all. I changed the gear oil in my differential. It was dark but I could see through it and I found no filings with a magnet. The noises are still there. I guess the bearings are next. Quote Link to comment Share on other sites More sharing options...
AKghandi Posted May 23, 2012 Share Posted May 23, 2012 (edited) Carrier bearing? I did one on a 92 loyale not even 2 days ago with the exact symptoms you decribe. It did seem to be louder on the pass side. and disappeared when in reverse Shake the drive shaft and see if its bad, the drive shaft shouldn't have any noticeable play, and it should turn easily. put it in 2wd and remove the 4 bolts holding the drive shaft to the rear diff, then turn it this is how bad mine was as you can see this car was horribly maintained and beaten senseless by somebody Edited May 23, 2012 by AKghandi Quote Link to comment Share on other sites More sharing options...
wentz912 Posted May 23, 2012 Share Posted May 23, 2012 I second the checking of the carrier bearing. Should also check the bushing above the rear diff. Helped replace one a couple weeks ago after discovering that it was NOT in fact a bad wheel bearing. Made god awful noise that we could hear from another car while at freeway speed! Quote Link to comment Share on other sites More sharing options...
opus Posted May 23, 2012 Share Posted May 23, 2012 And I 3rdly recommend....the drive shaft. Quote Link to comment Share on other sites More sharing options...
abcus Posted May 23, 2012 Author Share Posted May 23, 2012 Thanks for the help. I checked a few things but forgot to check the bushing above the differential. I raised the rear end up and let the wheels hang down. i tried to move the drive shaft up and down. It moved slightly, but there is rubber involved in the central carrier. It was not loose. should I be able to move it up and down at all ? Drive shaft turns smoothly when I rotate it. I can rotate it 1/4 inch before the wheels start turning. When I am at each rear wheel, and I change direction of rotation quickly, I hear a faint click noise. I did the spring vibration test again but did not feel anything this time. If I switch the brake drums, and if the noise does not follow the drum can i "assume" it is the bearing? I know i still have to check out the diff. bushing. Quote Link to comment Share on other sites More sharing options...
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