I think the guys that stole my car bottomed out over a big speed bump, 'cause now my u-joints are making horrid noises ALL the time. Seeing as the local shops want like, $250 to change my u-joints, I figure I might as well see if anyone has an aluminum driveshaft they wanna sell. Thanks for your help.
I think the guys that stole my car bottomed out over a big speed bump, 'cause now my u-joints are making horrid noises ALL the time. Seeing as the local shops want like, $250 to change my u-joints, I figure I might as well see if anyone has an aluminum driveshaft they wanna sell. Thanks for your help.
It's possible the bump cracked a flange, etc, you gotta take a close look. $250 sounds pretty high... Easy job to change U-joints and the parts are around $25 each. Most times the used aluminum driveshaft will need U-joint replacement too [mine did]. If your driveshaft is ready to fall out, I have a spare steel one that was running fine in my '87 sitting on the side not being used.
Reading around, other people have said that the same sound could also be my wheel bearing in the back. >.< And if I'm gonna do that, I'm gonna do a full brake job, which sucks.
Reading around, other people have said that the same sound could also be my wheel bearing in the back. >.< And if I'm gonna do that, I'm gonna do a full brake job, which sucks.
Changing 9-bolt axle bearing isn't difficult, but it means pulling the axle, etc, then presssing the new ones on. If, however, the noise is caused by a damaged pinion bearing, your 9-bolt will likely be considered economically unrepairable, unless you have a blood relative in the mechanic business willing to tear down the whole third member. Given the recent abuse, a damaged rear might be likely. If so, a third or fourth gen 10-bolt is a cheap replacement [I prefer the 4th Gen, since the brakes are better]. Rears in these cars with 150-250K on the clock don't absorb much punishment...
Hmm. So it's not like the front wheels where there's a wheel bearing just right there? Crap. >.< Well, the specific noise sounds almost just like pinging. But instead of two marbles rolling around in a soup can, it sounds like two aerosol cans tapping each other. Only happens on acceleration and deceleration. Cruising and no movement is fine. Gonna take it to a shop and have 'em drive it around the block to see what it sounds like.
Well, after some highly scientific tests, I have come to realize that the noise isn't my u-joints. :cry: I shifted the car into neutral while the noise was happening and revved the engine. Noise stayed steady. So it's my rear axle bearings. If I do one, I might as well do both. I guess Timkin bearings and seals are available at autozone, for a great price, and I hear the Timkin's are the best. Anyone know what else I should replace/check/smash with a brick while I'm in there?
Uh, explain to me how pitting the car in neutral rules out the U-joints? If the vehicle is coasting you wont change the driveshaft speed by going to neutral. Rear wheel bearings usually "howl" when going out. Do you have a vibration along with the noise? If so I'm guessing U-joints or driveshaft.
Wow. I never even thought that far. I liked my scientific methods.
I coulda sworn I had done the same thing before too, and gotten a different result. Oh well. Maybe I should just leave the car alone for a few days. It's been all I've doing save eating or sleeping for the last week. >.<
Thanks for pointing out how dumb I was. Oh well. I have u-joints, and I have a jack with stands. All I need is a mediocre press (I don't like the hammer idea :S) and a butane can torch.
The noise has been with the car for a while now. But never constantly. It would only happen before when it was frigid cold outside, and would disappear for months at a time. Since I got it back after the theft, it's just been constant. So if it is the driveshaft, then there's a great chance it's the u-joints, and not the whole shaft.
Some people say it does sound like U-joints, and if it is, it's gatta be the rear one, because that's where all the noise is coming from. If it's not the u-joints... Well, looks like I'll be taking apart the nine-bolt. Because I know the engine and tranny are fine, so it's from there back. Torque arms good too.
Anyways, thanks for giving me hope tom. I need it right now.
[quote=TheScaryOne;3392600]I have u-joints, and I have a jack with stands. All I need is a mediocre press (I don't like the hammer idea :S) and a butane can torch.
The noise has been with the car for a while now. But never constantly. It would only happen before when it was frigid cold outside, and would disappear for months at a time. Since I got it back after the theft, it's just been constant. So if it is the driveshaft, then there's a great chance it's the u-joints, and not the whole shaft.
Some people say it does sound like U-joints, and if it is, it's gotta be the rear one, because that's where all the noise is coming from. QUOTE]
Recommend changing both U-joints first if they're really old, since failure of those parts can be catastrophic. The process is simple, all that's needed is a vice large enough to press-in, press-out the U-joint. If the parts in there are original GM, you'll need to melt-out the nylon lockers first.
After doing that, if the noise isn't there any longer, fine. If the noise persists, put the car on a lift or on jack stands, run the engine, trans in drive and probe the rear end with a mechanics stethoscope to determine which side the noise is coming from.
My apologies if I came across as smug. Was not trying to show how dumb, or how smart I think I am. Thought you knew a secret on chasing noises I missed out on. You never mentioned any vibration. So I'm guessing you have none. Good idea to start with the U-joints. It may take a bit of work with the small torch to get the nylon locks out. Good luck. Oh, aside from bearings and gaskets. There really isnt much in the way of parts for 9 bolts out there.
Naw. Re-reading it I realized how dumb I sounded. Especially because I know I've refused to do that test for the reasons you said. It just made sense when I did it. And there wasn't even drinking. :P (Ed, Robert, Martin, hell, everyone who stayed at the kingman thirdgens I was at understands this perfectly. I told you not all my stories started with "when I was drunk...")
Well, when I took it to the tranny shop he teched the vibrations I was having as being a bad torque arm bushing. I replaced it, and no more bad vibrations. He said the noise might have been the torque arm rubbing on the driveshaft around the weight, but that obviously wasn't the case.
But yea. All it is is a noise. Sounds like I have two tin cans bouncing around under my car. Ting-ta-ting ting-ting-ta-ting. Kind of like metallic morse code.
The u-joints I bought are greaseable, should I get some solid ones instead? I hear the greaseable ones are significantly weaker than the solids.
I was just browsing around the aftermarket vendor review forum and found some new 9 bolt stuff listed. Probably not enough for a full rebuild, but enough to get the pig by until I can get a 10(12 in my dreams) bolt.
What is it in the 93+ 10 bolts that makes them wider with our wheels? Is it the axles? Could they be changed so they'd be correct width? That's what's really stopping my 10-bolt battle plan. I want a 7.625" with disc and a posi. Preferably disc-to-disc, and the more stock the car it came off of, the better. But I wanna run thirdgen wheels, and I don't want them to stick out.
Last edited by TheScaryOne : 07-09-2007 at 10:45 AM.
Greasable U-joints will be fine for your application. as far as the rear ends go. 4th gens. are wider overall. You cant change axles to narrow them up. And its still only a 7.5 inch 10 bolt. Do you have disc brakes now? PBR or Morane? Shouldnt be too hard to score a later 3rd gen. 10 bolt with PBRs. You can get gears and posi units aftermarket for them. Axles too if you need them. If worse comes to worse you can get an earlier 10 bolt with the Morane disc brake set up. For the price of a rebuild on the 9 bolt. It wouldnt be much more to up grade to a 9" Ford or 12 bolt from Strange or Moser.
"The u-joints I bought are greaseable, should I get some solid ones instead? I hear the greaseable ones are significantly weaker than the solids" -- Duck -- I don't think it matters unless you're doing burnouts all the time.
"I was just browsing around the aftermarket vendor review forum and found some new 9 bolt stuff listed. Probably not enough for a full rebuild, but enough to get the pig by until I can get a 10(12 in my dreams) bolt" -- Duck -- High labor cost is the problem with 9-bolt rears. Doesn't make sense to me to invest much money in a rear with limited availabilty, limited parts which are quite expensive, hard to find a mechanic experienced with those rears, and poor brakes. 10-bolt ThirdGen rears are only $100-200 at the salvage yards. That's a LOT cheaper than plowing $400-800 into the 9-bolt.
"What is it in the 93+ 10 bolts that makes them wider with our wheels? Is it the axles? Could they be changed so they'd be correct width? That's what's really stopping my 10-bolt battle plan. I want a 7.625" with disc and a posi. Preferably disc-to-disc, and the more stock the car it came off of, the better. But I wanna run thirdgen wheels, and I don't want them to stick out" -- Duck -- The 4th Gen rears have slightly longer 28-spline axles. My son's '92 Anniversary Z28 has a 4th Gen rear ... I like the more aggressive stance!
I could have sworn that the 7.625 came in the later years (90-92) while it was only the 7.5 for the earlier 10 bolts. And I only have the morane calipers, and they barely work. The backs have been adjusted. They just will not grip. Car braked like a dream for about a week after they were readjusted.
I found a lot of 10 Bolt Posi Disc rears on Car-Part.com, or whatever the used parts search engine is, problem is that shipping the damned thing would cost more than the rear. >.<
Only difference in the later 10 bolts was the axle spline. Went from 26 to 28. But I cant remember what year it changed. I believe the 9 bolt is the 7.625 inch ring gear. 10 bolts are 7.50 inches, 3rd or 4th gen..
Wow. I never even thought that far. I liked my scientific methods.
I coulda sworn I had done the same thing before too, and gotten a different result. Oh well. Maybe I should just leave the car alone for a few days. It's been all I've doing save eating or sleeping for the last week. >.<
Thanks for pointing out how dumb I was. Oh well. I have u-joints, and I have a jack with stands. All I need is a mediocre press (I don't like the hammer idea :S) and a butane can torch.
The noise has been with the car for a while now. But never constantly. It would only happen before when it was frigid cold outside, and would disappear for months at a time. Since I got it back after the theft, it's just been constant. So if it is the driveshaft, then there's a great chance it's the u-joints, and not the whole shaft.
Some people say it does sound like U-joints, and if it is, it's gatta be the rear one, because that's where all the noise is coming from. If it's not the u-joints... Well, looks like I'll be taking apart the nine-bolt. Because I know the engine and tranny are fine, so it's from there back. Torque arms good too.
Anyways, thanks for giving me hope tom. I need it right now.
dont forget about a slide hammer to remove the axles
Eh. If it winds up being the diff, I might just suck it up and buy a fourth gen rear from a local yard. Would prefer a thirdgen rear, though. Eventually I'm gonna suck it up and buy a 12 bolt, or maybe a Dana 44.
Well, changed my U-joints. Ended up having to take the driveshaft to a local shop. Paid $15 for the guy to press the old joints out and press the new ones in. Not that bad, really. Only went with the standard Neapco brand, but I don't plan on keeping the steel shaft for long.
Good news and bad news. New U-joints work perfect.
But.
The noise wasn't my U-joints. So it's my rear axle bearing. ^*$&
Think I'm gonna take out a student loan and buy a Strange Dana 60. If I'm upgrading, I might as well go the way of bulletproof, right? Gonna do some research on the posi they come with, see if it's gear or clutch type limited slip.
