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Discussion Starter · #1 · (Edited)
Hey all. We're getting some sounds from the rear drivers side (and sometimes, though less significant) other wheel areas on the car. I'm not really familiar enough with the noise to troubleshoot it effectively. You guys have any pointers? Perhaps unrelated, but the rear of the car also leans left a bit lower. Shock seems to be compressed 1/4-1/2 more than the right side. Would appreciate any feedback you guys have or any pointers to help troubleshoot or resolve it. It's keeping me from taking it any further than the neighborhood as I don't really feel safe driving it around until I can figure it out. For what it's worth, it doesn't happen until we've driven about a mile or so. No sounds on startup when it's cold. Just did a full brake flush and check on the rear drums, all looked good. Just excited to take her out on the road.

Video here (sorry for the low framerate, but sound should be good enough, especially if you toggle HD): PXL 20220508 174857774 GIF | Gfycat

And a photo of the leaning:
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I would get the car on a lift or raise the rear end and check the wheel for tightness...or cracks. Also, I would wiggle the wheel up and down and check for axle bearing play. It sounds like brake hardware loose in the drum or at the caliper....whatever you have. A visual inspection is needed of the axle and break hardware. Very common for rear wheel bearings to fail and make noise....if you have ANY play up and down or it is rough turning the wheel, it's a bad axle bearing. Could also be U-joints, but don't think so.
So: possible loose or cracked wheel, bad axle bearing, or loose/disconnected brake hardware.
 

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" as I don't really feel safe driving it around "

wheres your floor jack and lug wrench ???
and wheel chocks ?? jack stands...

park it where you can work on it... time to pull the rear tires n drums ....
hope it not your daily driver

either an axle bearing .,, and you will neeed an axle
if its that bad
or
someboby has been doing power break burnouts
and blew the brakes up ...

any fluid drips down the inside of your tire ?
if yes axle bearing probably
if no probable busted a backing plate to shoe stud and sheeits floppin around inside
 

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Discussion Starter · #4 ·
@geeteeohguy Thanks for the reply! Rear brakes are drums, and I just had it off earlier this week. Picture attached, though probably not the best. Aside from some dust that I tried to brush off after taking the pic (didn't want to aerosolize in the enclosed garage), the hardware looked pretty good / recently replaced. I guess I don't have a great frame of reference to compare it to a proper setup on the GTO, though. It's an automatic. With it in neutral I was having some difficulty rotating the wheels forward when they were up on the jack. Since this is my first time doing this type of work I don't really have a frame of reference for how easy those are to rotate normally when off the ground. Rims seemed in good condition and were tightened to 70ftlbs per the service manual afterwards. I'm not a big fan of the rims, would really like to get some Rally II replacements, but I can't imagine they would be causing that kind of noise?
 

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Discussion Starter · #5 · (Edited)
" as I don't really feel safe driving it around "

wheres your floor jack and lug wrench ???
and wheel chocks ?? jack stands...

park it where you can work on it... time to pull the rear tires n drums ....
hope it not your daily driver

Acquired them all! Had it jacked up earlier this week. Not my daily fortunately. Didn't see anything that looked out of the ordinary, but fairly untrained eyes here. As mentioned above the wheel had quite a bit of resistance in neutral jacked up though. Still really not sure what to compare it against.


any fluid drips down the inside of your tire ?
if yes axle bearing probably
if no probable busted a backing plate to shoe stud and sheeits floppin around inside
Haven't observed any leaks / fluid coming down any of the wheel area. Any other symptoms that would be a potential way to diagnose if that's the case?
 

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Im voting axle bearings, especially if it doesnt spin easy in neutral. Regardless... The car is 50 years old, so unless you know when the bearings were replaced last, then they should be done. Theyre always neglected. Easy to do if you have a press, or just pay a shop. Where are you located?
 

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Discussion Starter · #7 ·
Im voting axle bearings, especially if it doesnt spin easy in neutral. Regardless... The car is 50 years old, so unless you know when the bearings were replaced last, then they should be done. Theyre always neglected. Easy to do if you have a press, or just pay a shop. Where are you located?
Though this ended up in a warehouse the last year or two, my understanding is it was maintained pretty well (and the rest of it seems to show it). Central Florida. No press, slowly picking up equipment for things as I work on them.

Would those wheels spin easily in neutral even with the automatic transmission?
 

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Yes, if both are off the ground and you have a limited slip. If you have an open rear end, only one needs to be off the ground. You can jack the car up and if you can wiggle the wheel the axle bearing is shot. And, like others said, with these cars, if the bearing is sloppy, 99% of the time it takes out the axle and you will need a new axle and a new bearing. The bearings are sealed and 'lubricated for life' but tend to dry out and fail after many decades.
 

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If you're a fan of doing big burnouts it could also be what's left of your spider gears. But I believe you said it didn't happen all the time so it's not likely that. It's pretty easy to inspect the bearings though. It really only takes about 10 minutes to get one out.
 

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well now !!
thats great news you have had it up and checked ,,,, and she still clunks,,
good news bad news .... since/if that side looks dry BELOW the axle and the seal isnt leaking ...and you cant lift the axle hub UP and make it rattle up and down ,,,, in and out ... then its in the differential
time to pull the rear cover if you have not done it since you have had it ,,,
and do a drain clean and new lube
Scott
 

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I dont see the car bucking/moving when it clunks ,,, but it doesnt take much slop at the lugs to clunk .... but it seems to be a popping sound more
that still makes me want to pull the tire again

check lugnuts in the wheel fitment
then go to the lube ,,, and If I had never changed it I would still do it
be careful scooping the oil out of the bottom of the carrier DO not use your finger to pull the lube out as there could be metal shavings on the bottom against the case and they are sharp if they are there ... just me ,,,,
 

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dammm almost sounds like a busted axle ... gotta get it in the air again
but it should be leaking,... but the click it makes sounds like its coming from
the wheel .... are those unilug ?? I have had bad axle bearing before and one never clunked like that they all were grinding sounds like bad brake shoes
but
with that background engine noise it might be a tad hard to hear as it went out .. hmmmmm probably not the axle bearing if its not leaking/weeping
or its low on lube ....
the 2 oclock and 5 oclock lug studs look kinda beat up .... makes me wanna look at the wheel again

and that wheel cylinder is weeping also ..
the big sandy gritty debris sitting on the wheel cylinder and about is suspect also
 

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I see what appears to be air shocks. If you only have a single line connecting them, the car can lean when on shock pushes more on one side than the other - especially if they are used to support the car up because your coil springs are weak. Try putting more air in the shocks and see if that changes anything.

The car seems to sit a little low. This can affect drive shaft/pinion angle. Check that your u-joints are good and not shot and that the u-bolts are not hitting anything.

It could be a wheel bearing. Simple enough to check as Pontiac rear ends don't use C-clips like Chevy. You can pull the drum and inspect the brakes again. Then pull the axle - 4 bolts to remove and slide it out.

Watch this video. Skip up to the 4:00 and go to 6:00, and then skip to 9:08 to 11:00 and that will give you all you need to know on how to remove it and the bearings - which a shop will remove/install with a press.

You also want the 4-hole axle flange gaskets along with bearing/locking collar if you need to replace it. Fel-Pro makes these.

 

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Discussion Starter · #15 ·
good thinking on the pictures ,,,,also it sounds like to me that it may
be the wrong lug nuts,,, how about a picture of them????
ovaled holes no washers etc .... ???
They are ovaled holes with washers. Actually I really hate the rims and want to find some Rally II replacements when I can. Just prioritizing getting her 'safe' first.
 

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Discussion Starter · #16 ·
I see what appears to be air shocks. If you only have a single line connecting them, the car can lean when on shock pushes more on one side than the other ...

Thanks @PontiacJim ! I've been watching my fair share of videos and learning a hell of a lot from them. I'll add this to watch through next. Plan on doing as much of the work as I'm physically able -- and as long as the tools aren't for a specific use and expensive 😅
 

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Discussion Starter · #17 ·
Here's a close up of the rims. I don't have a great one of them off unfortunately. Will try to get it back up on the jack later this week probably. Like I said, they are ovaled holes underneath the lugnuts.
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Discussion Starter · #18 ·
Turns out they're called unilug style? Looking up videos of loose / bad wheel lugs and that's absolutely what it sounds like. Video here for reference:

What do you guys think? I wasn't planning on dropping the money on new rims just yet but that sure sounds exactly like what's happening here
 

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Those oval holes should have inserts. Uni lugs were popular (sort of) because you could use the same wheel with different wheel patterns. Just change the insert. If you don't have the inserts the wheel will not tighten up to the hub.
 

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Turns out they're called unilug style? Looking up videos of loose / bad wheel lugs and that's absolutely what it sounds like. Video here for reference:

What do you guys think? I wasn't planning on dropping the money on new rims just yet but that sure sounds exactly like what's happening here
You can get wheels cheap, but correcting what you have will also be cheap and easy. You just need the right lugs, if that's in fact the issue.

WHy don't you get a set of cheap, used steel wheels and put em on, see if the noise stops. If so, then you can decide whether or not you want to spend more.
 
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