Rear Axle replacement
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Thread Starter
Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
Well I checked the nuts today and they were a little loose so I tightened them but the noise is still there. It's too hot to tear into this tonight I'm going to take a look at it early sat. morning. Thanx guys. 
Thread Starter
Le Mans Master
Joined: Jun 2011
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From: Charlotte NC
St. Jude Donor '14-'15
I'm thinking you may have an issue with your differential rather than the axle itself. While making over 3000 low 10 second passes with stock axles on my cars, I've only ever snapped one a grand total of two times. In both cases the axles were never noisy or clunky prior to them breaking.
What I have however seen 4 or 5 times (both with my cars and others that I've worked on) is things start to get sloppy inside the differential, particularly the output shafts which is what the inner portion of the axle slides in to.
What I'd recommend you do is jack up the car again but this time when you attempt to move the axle back and forth, try to have somebody else hold it steady - first from the shaft and then at the inner cup where it goes into the differential.
The goal here is determine what exactly is making the clunking sound. If you can still move the axle back and forth while somebody else is trying to hold it steady from either spot then it probably is bad. If however you find that it's difficult or impossible to move it back and forth while somebody is holding it and you don't start hearing the clunking sound until the other person lets go, then your differential is likely the issue in this case.
What I have however seen 4 or 5 times (both with my cars and others that I've worked on) is things start to get sloppy inside the differential, particularly the output shafts which is what the inner portion of the axle slides in to.
What I'd recommend you do is jack up the car again but this time when you attempt to move the axle back and forth, try to have somebody else hold it steady - first from the shaft and then at the inner cup where it goes into the differential.
The goal here is determine what exactly is making the clunking sound. If you can still move the axle back and forth while somebody else is trying to hold it steady from either spot then it probably is bad. If however you find that it's difficult or impossible to move it back and forth while somebody is holding it and you don't start hearing the clunking sound until the other person lets go, then your differential is likely the issue in this case.
There is a little play when I turned the rotor by hand and it seems to be equal on both side. i hear some clunking sound and it seems to be a hollow sound. I held the shaft end at the rear and turned the rotor and found no significant looseness. The driver side was a little looser, I replaced that wheel hub a couple of months ago. I did one wheel at a time, put the jack under the lower ball joint and raised the rotor up to about normal ride height and checked again no real looseness. I then used a piece of wood to wedge against the lower control arm and the shaft , noticed little movement up and down at the joint (universal) the driver side had a little more play. I started the car and put it in drive and checked both ends of the shaft on both sides using my stethoscope and did not hear any unusual noise. The passenger side wheel bearing might be starting to wear but nothing to address right now. I shifted the trans back and forth from drive to reverse and heard no noise at idle.
I put the wheels back on and drove the car using the paddle shift, staying in 2nd gear pushing on the gas and releasing, multiple time to see if I could create a clunk (like the old days checking U joints) but everything was good.
It still makes a clunk that my wife could hear from 15 feet away but only when I make my initial start forward in drive. Any ideas? I wish I had another corvette to compare my to.
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So I jacked the car up today and put it on stands with the wheels off and the wheels hanging. I put lug nuts on the rotors so they were tight and would not make any noise.
There is a little play when I turned the rotor by hand and it seems to be equal on both side. i hear some clunking sound and it seems to be a hollow sound. I held the shaft end at the rear and turned the rotor and found no significant looseness. The driver side was a little looser, I replaced that wheel hub a couple of months ago. I did one wheel at a time, put the jack under the lower ball joint and raised the rotor up to about normal ride height and checked again no real looseness. I then used a piece of wood to wedge against the lower control arm and the shaft , noticed little movement up and down at the joint (universal) the driver side had a little more play. I started the car and put it in drive and checked both ends of the shaft on both sides using my stethoscope and did not hear any unusual noise. The passenger side wheel bearing might be starting to wear but nothing to address right now. I shifted the trans back and forth from drive to reverse and heard no noise at idle.
I put the wheels back on and drove the car using the paddle shift, staying in 2nd gear pushing on the gas and releasing, multiple time to see if I could create a clunk (like the old days checking U joints) but everything was good.
It still makes a clunk that my wife could hear from 15 feet away but only when I make my initial start forward in drive. Any ideas? I wish I had another corvette to compare my to.
There is a little play when I turned the rotor by hand and it seems to be equal on both side. i hear some clunking sound and it seems to be a hollow sound. I held the shaft end at the rear and turned the rotor and found no significant looseness. The driver side was a little looser, I replaced that wheel hub a couple of months ago. I did one wheel at a time, put the jack under the lower ball joint and raised the rotor up to about normal ride height and checked again no real looseness. I then used a piece of wood to wedge against the lower control arm and the shaft , noticed little movement up and down at the joint (universal) the driver side had a little more play. I started the car and put it in drive and checked both ends of the shaft on both sides using my stethoscope and did not hear any unusual noise. The passenger side wheel bearing might be starting to wear but nothing to address right now. I shifted the trans back and forth from drive to reverse and heard no noise at idle.
I put the wheels back on and drove the car using the paddle shift, staying in 2nd gear pushing on the gas and releasing, multiple time to see if I could create a clunk (like the old days checking U joints) but everything was good.
It still makes a clunk that my wife could hear from 15 feet away but only when I make my initial start forward in drive. Any ideas? I wish I had another corvette to compare my to.
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Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
Worst case scenario what would it cost to replace the output shaft? Does it require dropping the entire rear sub-frame? Could I do this myself?
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Dropping the subframe and getting the differential out isn't that tough (I wrote a how to guide for it), but replacing the output shaft requires rebuilding the diff which you need specialized tools for.
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
I am wanting to do this as I am going to go with a 3.15 in my C6 soon and was contemplating doing the job myself, as I do all my others work
Thanks,Matt
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Subfloor - Could I get a copy of the guide or a link to the "How To Guide for Removing the Differential in the C6"?
I am wanting to do this as I am going to go with a 3.15 in my C6 soon and was contemplating doing the job myself, as I do all my others work
Thanks,Matt
I am wanting to do this as I am going to go with a 3.15 in my C6 soon and was contemplating doing the job myself, as I do all my others work
Thanks,Matt
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Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Thanks,Matt
Le Mans Master
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From: Montreal
St. Jude Donor '13
Dropping the diff without the trans is no problem. Just don't forget the oring between them when putting it back. Seen that done and its not fun. LOL
I changed the output shafts on mine. Not that difficult to do.
I changed the output shafts on mine. Not that difficult to do.
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Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
Well it still has a clunk when the car is cold. Driving today it feels like the rear end of the car is loose almost like the back half of the car moves side to side. I just removed the driver side axle and I can find nothing wrong, tomorrow I will pull the passenger side and see what it looks like. I called a local Corvette mechanic and I'm going to ask him how much to drop the rear out, I'm afraid to ask really. I don't know if I can pull the rear out myself on the floor in my garage with jack stands. 
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Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
driver side back together and wheel is on, I'm thinking I could do this job with my eyes closed now. Hopefully I find an issue on the passenger side tomorrow, just way too hot to work. 
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Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
Passenger side is OK but the wheel bearing is a little dry so I am going to replace it before putting the shaft and wheel back together. Now I need to make a decision.
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Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
I was under the car and I had someone move the wheel back and forth while looking for the noise and there is a clicking sound coming directly where the trans and rear come together, I can feel it with my fingers. What is in there an input shaft and what else? Chevy replaced my TCM like 2 years ago, does the trans need to come out to do that? I know it's nothing they did just trying to figure out what is going on. Mechanic said he can't get to it for 3 weeks.
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Le Mans Master
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From: Charlotte NC
St. Jude Donor '14-'15
I just read you DIY and looked at the pic's.
So how high up off the ground does the car need to be?
4 jack stands to hold the car up?
1 jack stand under the motor?
What type of jack do I need to keep under the trans?
drop the rear sub frame with the diff attached to the trans and then seperate the two leaving the trans on a jack?
Do I have this correct?
So how high up off the ground does the car need to be?
4 jack stands to hold the car up?
1 jack stand under the motor?
What type of jack do I need to keep under the trans?
drop the rear sub frame with the diff attached to the trans and then seperate the two leaving the trans on a jack?
Do I have this correct?
Thread Starter
Le Mans Master
Joined: Jun 2011
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From: Charlotte NC
St. Jude Donor '14-'15
quiet here.......
I changed the rear gear oil with the OEM like suggested, bought 3 quarts because I read that you can't get all the oil out of the bottle well I did, bought some extra hose and an right angle, actually stood outside of the wheel well and added 2 quarts complete (see tool). I also bought some amuminum brightner and cleaned the spindle, WOW that stuff works good. See before and after shots.
I changed the rear gear oil with the OEM like suggested, bought 3 quarts because I read that you can't get all the oil out of the bottle well I did, bought some extra hose and an right angle, actually stood outside of the wheel well and added 2 quarts complete (see tool). I also bought some amuminum brightner and cleaned the spindle, WOW that stuff works good. See before and after shots.