C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

72 vette rear end issue

Thread Tools
 
Search this Thread
 
Old 09-18-2013, 10:29 PM
  #1  
Jhiltonn
Racer
Thread Starter
 
Jhiltonn's Avatar
 
Member Since: Apr 2013
Posts: 415
Received 9 Likes on 9 Posts

Default 72 vette rear end issue

I bought my 72 vette in March of this year. It's got 89k miles on it and I've only driven it approx 300 miles to date. I've been busy replacing many parts this year such as new exhaust system, new HEI distributor, new plugs and wires, new flywheel, clutch, front end bushings, rear end bushings, strut rods, tires, brakes, PS hoses, basically all new rubber bushings except I haven't changed the A-Arm bushings, nor the rear trailing arm bushings. I also removed the windshield and fixed the birdcage frame with some patch welding then rust proofed the WS frame plus the entire car's frame inside and out with Eastwood rust products, all new weatherstripping, changed the tranny oil, new front bearing in the M-20 tranny and changed out the rear end oil and added posi-lube too. The rear end initially was making noises, but after chg the oil, I did 24 figure 8's in a parking lot and the rear end noise went away. My buddy who's been helping with some of the harder items since he's got a car repair shop, says the rear wheel bearings on my drivers side is bad, as are the trailing arm bushings on the back too, especially the drivers side bushing. If you look at the car from the rear while on a lift, the drivers side wheel is leaning out quite a bit more than the pass side wheel. Then if you look at the half shaft on the drivers side, you can see about half inch of shiny metal on the shaft's end, right where it goes into the differential. On the pass side, you don't see this shiny metal end. He's told me that the wheel bearing is shot on that side as you can move the wheel back and forth if you shake it, going 9 to 3. Plus the fact you can see this clean, shiny metal end of the half shaft....he told me not to drive it fast, nor put too many miles on it, until I can afford to pay for new rear wheel bearings, new trailing arm bushings, 6 new u-joints, and possibly drop the differential this winter. So my question is this... Is it dangerous to drive the car with these issues on the rear end? I haven't driven it much at all since I bought it, and now that I've fixed many issues with the car, I worry if I drive it too much before we address these issues, can I cause more damage? The last couple of times I've driven the car 20 miles into town, I've heard a loud clunk noise once or twice coming from the rear end. Lastly, this fall/winter are there any other items I need to inspect/replace around the rear end area of the car, as I'm planning on addressing the above issues as the rear end will probably be out of the car at that time? My buddy's not a corvette specialist, so should I seek out a corvette specialist in southern NH to do the work? My friend's garage is a general type shop but he gives me free time on nights and weekends to use one of his lifts, plus when I need his help, he's very reasonable with his time. I do want it done right, maybe I can remove the parts that need fixing, then drop them off at a specialist and reinstall myself? I'm on a tight budget too. What do you experts think is the correct approach? Many thanks and sorry for rambling on so much! Joe
Old 09-18-2013, 10:58 PM
  #2  
Jhiltonn
Racer
Thread Starter
 
Jhiltonn's Avatar
 
Member Since: Apr 2013
Posts: 415
Received 9 Likes on 9 Posts

Default

Here's the only picture I have of the drivers side wheel, which you can see in the picture below that it's leaning out more than the other side. I don't currently have a pic showing the half shaft and the 1/2" shiny metal end, but can get one if needed. thanks again, Joe
Old 09-19-2013, 09:27 AM
  #3  
wombvette
Le Mans Master
 
wombvette's Avatar
 
Member Since: Jan 2000
Location: New Hill NC
Posts: 8,918
Likes: 0
Received 24 Likes on 23 Posts

Default

The keeper is off of the side that slides out of the rear end. That in itself is not a real problem for driving, unless you are going to race it. The shaft does not slide out in normal operation.

Now the question is why its out. Some rears, mostly mid seventies, have a problem with stub axle wear. The end of the shaft wears off and the keeper will fall off. It is unusual for a 72, but possible. If that is happening, you should take care of it, by installing hardened shafts and checking out the rear for further damage. Look to see if the U-bolts have hit the rear housing. That is a sigh the axles are receding.
Old 09-19-2013, 09:31 AM
  #4  
doorgunner
Nam Labrat

Support Corvetteforum!
 
doorgunner's Avatar
 
Member Since: Sep 2013
Location: New Orleans Loo-z-anna
Posts: 33,898
Received 4,178 Likes on 2,738 Posts

Default

In the "old days" at the dealership, we drained the diff./Refilled it with A/T fluid/drove the car around town-lots of turns for 30 minutes/drained A/T fluid thoroughly/refilled Diff. with correct Diff. Oil.

That method "scrubbed" all the build-up off the Diff. internal parts.

BUT WAIT FOR OTHER MEMBERS ADVICE concerning th A/T Fluid method!
Old 09-19-2013, 10:37 AM
  #5  
Mike Ward
Race Director
 
Mike Ward's Avatar
 
Member Since: Jul 2001
Posts: 15,892
Likes: 0
Received 30 Likes on 28 Posts

Default

Sorry, I had to do this, I was going cross eyed trying to read your post.

Originally Posted by Jhiltonn
I bought my 72 vette in March of this year. It's got 89k miles on it and I've only driven it approx 300 miles to date.

I've been busy replacing many parts this year such as new exhaust system, new HEI distributor, new plugs and wires, new flywheel, clutch, front end bushings, rear end bushings, strut rods, tires, brakes, PS hoses, basically all new rubber bushings except I haven't changed the A-Arm bushings, nor the rear trailing arm bushings.

I also removed the windshield and fixed the birdcage frame with some patch welding then rust proofed the WS frame plus the entire car's frame inside and out with Eastwood rust products, all new weatherstripping, changed the tranny oil, new front bearing in the M-20 tranny and changed out the rear end oil and added posi-lube too.

The rear end initially was making noises, but after chg the oil, I did 24 figure 8's in a parking lot and the rear end noise went away. My buddy who's been helping with some of the harder items since he's got a car repair shop, says the rear wheel bearings on my drivers side is bad, as are the trailing arm bushings on the back too, especially the drivers side bushing.

If you look at the car from the rear while on a lift, the drivers side wheel is leaning out quite a bit more than the pass side wheel. Then if you look at the half shaft on the drivers side, you can see about half inch of shiny metal on the shaft's end, right where it goes into the differential. On the pass side, you don't see this shiny metal end.

He's told me that the wheel bearing is shot on that side as you can move the wheel back and forth if you shake it, going 9 to 3. Plus the fact you can see this clean, shiny metal end of the half shaft....he told me not to drive it fast, nor put too many miles on it, until I can afford to pay for new rear wheel bearings, new trailing arm bushings, 6 new u-joints, and possibly drop the differential this winter.

So my question is this... Is it dangerous to drive the car with these issues on the rear end? I haven't driven it much at all since I bought it, and now that I've fixed many issues with the car, I worry if I drive it too much before we address these issues, can I cause more damage?

The last couple of times I've driven the car 20 miles into town, I've heard a loud clunk noise once or twice coming from the rear end. Lastly, this fall/winter are there any other items I need to inspect/replace around the rear end area of the car, as I'm planning on addressing the above issues as the rear end will probably be out of the car at that time?

My buddy's not a corvette specialist, so should I seek out a corvette specialist in southern NH to do the work? My friend's garage is a general type shop but he gives me free time on nights and weekends to use one of his lifts, plus when I need his help, he's very reasonable with his time. I do want it done right, maybe I can remove the parts that need fixing, then drop them off at a specialist and reinstall myself?

I'm on a tight budget too. What do you experts think is the correct approach? Many thanks and sorry for rambling on so much! Joe

The only significant thing I see is the rear wheel bearing play when the wheel is moved at 3-9 o'clock. Investigate and confirm this first.

As Wayne says, the yoke moving in and out of the diff is not a big deal. It's certainly not a safety issue. There's lots of C2/C3 Corvettes that are in the same condition whether the owners know it or not.
Old 09-19-2013, 11:28 AM
  #6  
MelWff
Race Director
 
MelWff's Avatar
 
Member Since: May 2006
Posts: 16,217
Received 1,817 Likes on 1,606 Posts

Default

"The last couple of times I've driven the car 20 miles into town, I've heard a loud clunk noise once or twice coming from the rear end."

Check the two rubber bushings on the nose of the differential where it bolts to the frame.
Old 09-21-2013, 11:34 PM
  #7  
Jhiltonn
Racer
Thread Starter
 
Jhiltonn's Avatar
 
Member Since: Apr 2013
Posts: 415
Received 9 Likes on 9 Posts

Default

Thanks everyone! Much appreciated!! I checked the car when on the ground and the drivers side half shall isn't showing that shiny end, so I guess the inside clip is off on the inside of the differential. So the only way to remedy that is by removing the rear cover? Could the clip that's fallen off inside do any damage to the interior gears of the diff?

I also noticed when he car is on the ground, the drivers side shell is angled in at the top. Could this be from the shot front bushing on the drivers side trailing arm?

Get notified of new replies

To 72 vette rear end issue




Quick Reply: 72 vette rear end issue



All times are GMT -4. The time now is 10:42 AM.