Topic: Differential maintenance after gear swap
in Forum: C3 Driveline Components
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I having 3.70's swapped in. I've read the gear break in procedures but no mention of what type of oil to use during that period.
Anyone have suggestions on break in oil and what type to use after the 500 oil change?
Anyone have suggestions on break in oil and what type to use after the 500 oil change?
|B|76 X coupe |/B|
#s match - Classic White - Buckskin
|IMG|http://webpages.charter.net/equestrian/76x.gif |/IMG|
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Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
you use standard gear oil with posi additive before and after.. i would give it 1000 miles though..
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Portland, TN - USA
Joined: 4/29/2003
Posts: 805
Vette(s): 1972 Coupe
Anything, but Stock and more mods to come!
SSBC Force 10 Brakes, 3.73, TH350, 355 CID, Rack and Pinion, Vette Brakes suspension front and rear.
When I spoke to randy ring and pinion they told me you can break them in using 80W gear oil and posi slip lube mixed to the right portions.
I asked about synthetic they said you can break them in with syn, but it was a waste because you needed to dump the oil after 500 miles. So they said to run standard and then after the change they said would be a good time to run syn if you decided to go that way.
I asked about synthetic they said you can break them in with syn, but it was a waste because you needed to dump the oil after 500 miles. So they said to run standard and then after the change they said would be a good time to run syn if you decided to go that way.


Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
by the way.. if you havent installed it yet.. now would be a GREAT time to add a drain plug..
|UPDATED|9/29/2004 9:28:47 PM (AZT)|/UPDATED|
|UPDATED|9/29/2004 9:28:47 PM (AZT)|/UPDATED|
How much did it cost? I am considering uping my diff. Did you replace gears or total swap. How's the punch. Was it worth the $$. I have a 1980 with a crate 330 HP. 

|IMG|/member_uploads/6601_6700/6620/Vette018.JPG|/IMG|
Hey Relayer44. I just noticed your post.
The best price I found on ring and pinion gears with the install kit was about $300 and $100 for the install from a guy I met at the track. I did get some install quotes from shops in Dallas and they range from $400-$1000!
The best price I found on ring and pinion gears with the install kit was about $300 and $100 for the install from a guy I met at the track. I did get some install quotes from shops in Dallas and they range from $400-$1000!
|B|76 X coupe |/B|
#s match - Classic White - Buckskin
|IMG|http://webpages.charter.net/equestrian/76x.gif |/IMG|
in Forum: C3 Driveline Components
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