Differential lubricant for C3, alternative to ACDelco
- Thread starter Giu
- Start date
Roscobbc
Moderator
Have you tried Rock Auto?
Giu
Well-known user
My mechanic want it fast
johng
CCCUK Member
I used this in mine, it's been there for 4 years now with no issues. This is for a limited slip diff, not sure if that's what you've got.
Castrol TRANSMAX Limited Slip Z 85W-90 Mineral Axle Fluid
Castrol TRANSMAX Limited Slip Z 85W-90 Mineral Axle Fluid
Forrest Gump
CCCUK regional rep
There’s a guy in the States called Gary Ramadei (GTR1999 on the Corvette forum) who is considered THE expert on C3 differentials.
His recommendation is a 90 weight mineral gear oil (any brand) with, and this is the important bit, GM AC Delco additive.
There are alternatives, but you never know how they will behave with the diff clutch pack, so I would just stick with the tried and tested GM additive.
You can get that additive easily in the UK, from our supporting vendors I expect or other online suppliers like John Wolfe Racing. You need two bottles.
His recommendation is a 90 weight mineral gear oil (any brand) with, and this is the important bit, GM AC Delco additive.
There are alternatives, but you never know how they will behave with the diff clutch pack, so I would just stick with the tried and tested GM additive.
You can get that additive easily in the UK, from our supporting vendors I expect or other online suppliers like John Wolfe Racing. You need two bottles.
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Forrest Gump
CCCUK regional rep
Yes, but put the additive in first then fill up with the oil.
Mad4slalom
Well-known user
My mechanic want it fast
Ck have it in stock for next day deliv.
Probably gavin roe as well.
Mad4slalom
Well-known user
Have you thought about adding a diff drain plug while you are at it. Beats trying to suck out the old stuff and easy to flush through.
Giu
Well-known user
For now all in God hands, if the mechanic wants it, I'll give you a call right away, at the moment I don't want overlap suppliesCk have it in stock for next day deliv.
Probably gavin roe as well.
thank you for the offer, I really appreciate!!!
Giu
Well-known user
I bought a transfer pump /sucking pump. It's quite tempting the drain plug and a very good idea. but sadly there is no way they make it cheap for the labor.Have you thought about adding a diff drain plug while you are at it. Beats trying to suck out the old stuff and easy to flush through.
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Chuffer
CCCUK Member
The problem with trusting in God is heFor now all in God hands, if the mechanic wants it, I'll give you a call right away, at the moment I don't want overlap supplies
Chuffer
CCCUK Member
The problem with trusting in God is he`s not an engineer and therefore doesn`t know enough ! That`s why people hate engineers , they know too much .
Mad4slalom
Well-known user
Easy 40min job once you have the right drills and tap. Gavin roe talked me though it and it all went smoothly £20 in bits and your labour is free. Very satisfying job
Giu
Well-known user
Ok, everything Done thank you guys!!!! Funny story, the mechanic was puzzled cause there was no oil in the differential!!! my previous mechanic substitute the yoke gaskets nice job, but he forgot to fill up the Differential Lubricant!! Lucky me I did not push the car. This mech was able to put back the 1975 the end cap differential, when the previous mechanic said that was complicated after working on my car for over 9 months... this guy, one week, now I can use my spare rear spring... money saved!!!
Chuffer
CCCUK Member
Sounds like your first guy couldn`t even spell ` Mechanic` never mind actually be one !!!!