Yet another post about rear differential fluid...
Thread Starter
Race Director
Joined: Oct 2000
Posts: 17,102
Likes: 7
From: Fair Oaks, OK
Yet another post about rear differential fluid...
My vette's rear end makes some faint noises when turning, which I believe is the friction disks in the rear end. So I have 2 quarts of GM 80w 90 rear end lube and 2 bottles of GM posi additive.
I took my car to the local quick lube place today, and they told me they had nothing that could remove the old fluid. So, I went to one of my customer's auto repair shops. He had nothing that could suck out the old fluid, and said he "didn't want to work on any old corvettes". Went to another quick lube place and waited 20 minutes and nobody ever came to the counter. So as a last effort, I went to the local Chevrolet dealership, where they wanted a minimum of $70 to do the job.
Now I am bound and determined to do this job myself. What kind of pump do I need to take the old fluid out of my differential? Are there any tricks to getting the new fluid in the diff? It looks a little cramped in the area of the fill plug and I don't think I can get a quart bottle near the fill hole. Will I need to remove my spare tire carrier?
Any and all tips are appreciated.
On a side note, I sat in a '01 DBGM coupe today and started her up. Man those C5's are nice cars!!! Can't wait to add one to the stable.
I took my car to the local quick lube place today, and they told me they had nothing that could remove the old fluid. So, I went to one of my customer's auto repair shops. He had nothing that could suck out the old fluid, and said he "didn't want to work on any old corvettes". Went to another quick lube place and waited 20 minutes and nobody ever came to the counter. So as a last effort, I went to the local Chevrolet dealership, where they wanted a minimum of $70 to do the job.
Now I am bound and determined to do this job myself. What kind of pump do I need to take the old fluid out of my differential? Are there any tricks to getting the new fluid in the diff? It looks a little cramped in the area of the fill plug and I don't think I can get a quart bottle near the fill hole. Will I need to remove my spare tire carrier?
Any and all tips are appreciated.
On a side note, I sat in a '01 DBGM coupe today and started her up. Man those C5's are nice cars!!! Can't wait to add one to the stable.
Drifting
Joined: Nov 2003
Posts: 1,634
Likes: 4
From: Northern NJ
St. Jude Donor '04 & '05
Re: Yet another post about rear differential fluid... (Stoge)
You need some kind of suction pump/gun. Here's a link to an inexpensive one at Harbor Freight:
http://www.harborfreight.com/cpi/cta...emnumber=40828
I used something similar to do mine. Worked pretty well although it doesn't drain every last drop. However as long as you get the pickup to the bottom of the diff carrier, then most of it will come out which should be fine.
The only other way to remove the rear cover which isn't necessary IMO.
Good Luck!
[Modified by ACECO, 12:33 AM 7/7/2004]
http://www.harborfreight.com/cpi/cta...emnumber=40828
I used something similar to do mine. Worked pretty well although it doesn't drain every last drop. However as long as you get the pickup to the bottom of the diff carrier, then most of it will come out which should be fine.
The only other way to remove the rear cover which isn't necessary IMO.Good Luck!
[Modified by ACECO, 12:33 AM 7/7/2004]
Advanced
Joined: Jun 2004
Posts: 63
Likes: 0
From: North Canton Ohio
Re: Yet another post about rear differential fluid... (Stoge)
I use a hand operated oil suction gun from JC Whitney... P/N SF520017A... cost is $10.99 in my most recent catalog. After I got the vehicle on jack stands, I had to use, I believe, a 5/8" "crow's foot" on my 3/8" drive ratchet (11 pc. SAE set set is also available in JC Whitney catalog, P/N SF840924P for $9.99 - much cheaper than Sears) to remove/tighten drain plug. The suction gun has a piece of flexible tubing that I fed into the sight plug hole to the bottom of the diff. I kept sucking out old fluid until I couldn't get anymore, then I used the suction gun to pump in the new fluid and additive after cleaning it. I used two bottles of GM posi additive and Moroso synthetic gear lube (in place of the GM lube - available from Corvette Central). You simply add fluid until it starts to spill out of the sight plug. After changing the fluid, I drove the car to a parking lot and drove in tight circles in both directions to work the additive into the posi discs. Seems to have done the trick!
Good Luck!
Good Luck!
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Re: Yet another post about rear differential fluid... (Stoge)
Blahblahblah, yakkity yakkity. Any guy who thinks that changing differential oil in an old corvette is hard is an i-d-i-o-t!!!
Pop the cover with a combo wrench, use a vacuum pump to suck out the old fluid, and you are good-to-go.
I did this by only dropping the spare carrier- did not have to raise the car off the ground.
-Steve
Pop the cover with a combo wrench, use a vacuum pump to suck out the old fluid, and you are good-to-go.
I did this by only dropping the spare carrier- did not have to raise the car off the ground.
-Steve
Thread Starter
Race Director
Joined: Oct 2000
Posts: 17,102
Likes: 7
From: Fair Oaks, OK
Re: Yet another post about rear differential fluid... (Pacin'California)
Blahblahblah, yakkity yakkity. Any guy who thinks that changing differential oil in an old corvette is hard is an i-d-i-o-t!!!
The way I look at it, he doesn't want to work on Corvettes, FINE!!! He's not going to get any of my $$$.
FWIW, I'm going to buy one of those $10 hand pumps like the links above and be done with it.
Racer
Joined: Jul 2002
Posts: 264
Likes: 0
From: Franklin Ohio
Not too tough
I just changed the fluid on my 68 and it wasn't hard. Took off the passenger side rear wheel and was able to use a couple long extentions on a 3/4 inch socket to remove the plug. Used the old turkey baster and tube to suck it out then used the same tube on the end of the limited slip fluid and gear lube for the refill. I dropped my spare but didn't need to.
Racer
Joined: Dec 2007
Posts: 445
Likes: 2
From: Thomastown Mississippi
It's an easy job. On my '77, I do it without jacking the car or removing the rear wheel. As posted above, you can remove the plug with a couple of extensions. The first time I did this years ago, I refilled the rear end with the right side jacked up. It actually overfilled it and gear oil seeped out around the spindles. When I change it now, I do it on flat surface and refill to the bottom of the plug hole.
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