I wish I had replaced mine with a rubber bushing as well. I sometime think I can hear some resonance coming through the poly mount.
differential mounting "cushion" install
Thread Starter
Burning Brakes
Joined: Jul 2008
Posts: 876
Likes: 0
From: Canastota Ny
differential mounting "cushion" install
Doing a fluid change this weekend. Can the mount for the front of the rear diff be replaced by just removing and replacing or will the rear end tilt forward or have any adverse affects?
Jack it or leave on the ground?
thanks guys!
Jack it or leave on the ground?
thanks guys!
Melting Slicks
Joined: Apr 2008
Posts: 2,623
Likes: 242
From: Russell Ontario
St. Jude Donor '09
I did a few on the hoist but it can be done easily on the ground with the car jacked up , you will need a wrench on the top to hold the bolt or nut depending how it was put on. should only take 1/2hr to do , just take your time and make sure you use jack stands the bolt is fairly tight! I find the upper mount is the one to go!
Some times it's a little tricky to get the bolt out cause of the driveshaft
, keep us updated! Ron
Some times it's a little tricky to get the bolt out cause of the driveshaft
, keep us updated! Ron
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
The top of the differential is bolted to the crossmember and the crossmember is bolted to the frame, so if your differential moves that would indicate loose bolts somewhere. You might have to pry the tongue down slightly to get the new mount in. If you have a lift available the job will be a lot easier but you can use ramps or jackstands.
I used a poly front mount but I think if I were to do it again I would use rubber instead.
Rick B.
I used a poly front mount but I think if I were to do it again I would use rubber instead.
Rick B.
Thread Starter
Burning Brakes
Joined: Jul 2008
Posts: 876
Likes: 0
From: Canastota Ny
great to hear guys! 
im "lift" challenged so jack stands and floor jack it is plus im fairly skinny too so geting under it should be okay. i also purchased the additive for the rear diff today. but the was a bit weary on the weight of the actual gear fluid itself. shouldnt it be 90W?
im "lift" challenged so jack stands and floor jack it is plus im fairly skinny too so geting under it should be okay. i also purchased the additive for the rear diff today. but the was a bit weary on the weight of the actual gear fluid itself. shouldnt it be 90W?
Melting Slicks
Joined: Aug 2005
Posts: 2,683
Likes: 34
From: Working on the car NY
I did the cushion on my '67 quite a while back and remember something to the effect of having a hell of a job compressing the cushion. Maybe I needed a longer bolt or something but I eventially jacked the car up enough to compress the cushion to get the bolt on.
Drifting
Joined: Jan 2001
Posts: 1,841
Likes: 3
From: Halifax, NS, Canada
Terrorizing Orange Cones
Joined: Oct 2007
Posts: 2,572
Likes: 17
From: Northern CO
If I understand your question correctly, you mean the 2 piece 'cushion' set for the mount bolted on the 'chin' of the differential? Not too difficult to perform but each experience is always different.
Once you secure the car with jackstands, Ron Rail is right about unbolting the driveshaft to gain enough clearance. Mine had a large washer & nut on bottom so the bolt was removed from above the frame mount. There is (should be) a steel sleeve through the 2 cushions; may need a few squirts of your favorite penetrating oil to coax apart. The bolt has a large fender washer that compresses the top bushing against the frame mount. I didn't have any problems leveraging mine apart and protect your eyes from all the dirt that you loosen. I expect there will be plenty.
Hope that helps. I can offer my take if it is the main support the top rear of the differential is bolted to. That one is just a little more involved; LOL.
Good Luck and let us know how it went.
Once you secure the car with jackstands, Ron Rail is right about unbolting the driveshaft to gain enough clearance. Mine had a large washer & nut on bottom so the bolt was removed from above the frame mount. There is (should be) a steel sleeve through the 2 cushions; may need a few squirts of your favorite penetrating oil to coax apart. The bolt has a large fender washer that compresses the top bushing against the frame mount. I didn't have any problems leveraging mine apart and protect your eyes from all the dirt that you loosen. I expect there will be plenty.
Hope that helps. I can offer my take if it is the main support the top rear of the differential is bolted to. That one is just a little more involved; LOL.
Good Luck and let us know how it went.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
Pro
Joined: May 2006
Posts: 576
Likes: 0
From: Kernersville North Carolina
great to hear guys! im "lift" challenged so jack stands and floor jack it is plus im fairly skinny too so geting under it should be okay. i also purchased the additive for the rear diff today. but the was a bit weary on the weight of the actual gear fluid itself. shouldnt it be 90W?
im "lift" challenged so jack stands and floor jack it is plus im fairly skinny too so geting under it should be okay. i also purchased the additive for the rear diff today. but the was a bit weary on the weight of the actual gear fluid itself. shouldnt it be 90W?It should take two of the 80W-90 and two of the differential additive. i'm doing all of my work on 4 jack stands with 2 floor jacks. makes for a lot of fun and many interesting stories of how you get a lot of injuries!
Thread Starter
Burning Brakes
Joined: Jul 2008
Posts: 876
Likes: 0
From: Canastota Ny
if its the block thing, sandwiched in metal attached to the center of the spring, then that is new.i just changed out the fluid tonight. went very smooth i even found (under all the grunge) the original fill tag thingy that says to use only posi fluid!
1st Gear
Joined: Aug 2008
Posts: 1
Likes: 0
I just did the universals on the driveshaft last weekend, Chiltons suggested using a block of wood as a wedge between the top of the differential carrier and the car floor to keep the carrier from twisting on its rubber mounts. I did not know what they were talking about, but I found out the hard way. If you are going for those front large rubber biscuts, stick a piece of 2x4 between the differential and the car floor, or better yet do not disconnect the universals. I am probably going to have to rebuild the differential in the not to distant future. So I will replace those biscuts with the rubber then.
Cheers 2U TonyK.
Cheers 2U TonyK.
Thread Starter
Burning Brakes
Joined: Jul 2008
Posts: 876
Likes: 0
From: Canastota Ny
I just did the universals on the driveshaft last weekend, Chiltons suggested using a block of wood as a wedge between the top of the differential carrier and the car floor to keep the carrier from twisting on its rubber mounts. I did not know what they were talking about, but I found out the hard way. If you are going for those front large rubber biscuts, stick a piece of 2x4 between the differential and the car floor, or better yet do not disconnect the universals. I am probably going to have to rebuild the differential in the not to distant future. So I will replace those biscuts with the rubber then.
Cheers 2U TonyK.
Cheers 2U TonyK.
atleast if i ever sell the car i will have a list of work done and receipts. Several for parts and labor and one for a 2x4
Instructor
Joined: Apr 2005
Posts: 203
Likes: 20
From: Madison Indiana
Where do you get the rubber version? I've only found the poly one on the vendor's websites. My '69 is making a clunking noise, and after surfing through the archives, replacing that bushing might be the solution. Thanks!
Pro
Joined: May 2006
Posts: 576
Likes: 0
From: Kernersville North Carolina
I purchased my entire suspension group from Volunteer Vette Products. The only items they currently do not have in rubber are the sway bar bushings.
