Diff Fluid from Factory
Melting Slicks
Joined: Apr 2009
Posts: 2,479
Likes: 36
Thread Starter
Le Mans Master
Joined: Feb 2003
Posts: 6,683
Likes: 144
From: Memphis Tennessee
Drifting
Joined: Apr 2007
Posts: 1,496
Likes: 1
From: LEBANON PA.
Hi There;
The original fluid was gm p/n 12378261 which is a synthetic. I,am guessing that you want to change the factory fluid out.
I used amsoil severe gear 75w-90 synthetic extreme pressure lub. I bought their pump g-2039 for $11.76 2qts. of gear oil (6spd) $21.20.You will need a t-55 torx for both plugs.System holds 1.69 qts. fill with the car level until the fluid runs out the fill hole.This pump works very well & no spilled fluid to clean up.Pump only works on the amsoil bottles. The pump kit also contains 3 white adapters to fit bottle sizes 1qt, 1 gal, 2 1/2gal. BTW the old g/oil really stinks.
Have fun
robsc501
The original fluid was gm p/n 12378261 which is a synthetic. I,am guessing that you want to change the factory fluid out.
I used amsoil severe gear 75w-90 synthetic extreme pressure lub. I bought their pump g-2039 for $11.76 2qts. of gear oil (6spd) $21.20.You will need a t-55 torx for both plugs.System holds 1.69 qts. fill with the car level until the fluid runs out the fill hole.This pump works very well & no spilled fluid to clean up.Pump only works on the amsoil bottles. The pump kit also contains 3 white adapters to fit bottle sizes 1qt, 1 gal, 2 1/2gal. BTW the old g/oil really stinks.
Have fun
robsc501
Last edited by robsc501; Oct 11, 2009 at 10:16 PM.
Thread Starter
Le Mans Master
Joined: Feb 2003
Posts: 6,683
Likes: 144
From: Memphis Tennessee
I only have 30K on the clock, but in the next few months I am going to change it out just because. I will either use Mobil 1 or just go back with the stock stuff.
I have the normal "whine" the is typical with this gearbox, even had it in my 94 Trans Am GT, kinda used to it now.....actually cut-outs did make it better LOL. Probably won't make any difference with the noise, but I will know that it is good for another 30 to 40K of fun.
Thanks for the suggestions.
I have the normal "whine" the is typical with this gearbox, even had it in my 94 Trans Am GT, kinda used to it now.....actually cut-outs did make it better LOL. Probably won't make any difference with the noise, but I will know that it is good for another 30 to 40K of fun.
Thanks for the suggestions.
Melting Slicks
Joined: Apr 2009
Posts: 2,479
Likes: 36
After searching many threads in many online forums, I decided to stick with the GM fluid and additive for the diff. It seems to be an excellent synthetic gear lube. The transmission was another story. I went with Mobil 1 synthetic ATF in my manual tranny and I am glad I did. The difference in shifter smoothness was remarkable.
