80w90 or What?
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From: Chemainus, Bristish Columbia, Canada
Car: 1991 GTA Trans AM
Engine: 305 TPI V8
Transmission: 4-Speed Automatic (700-R4)
Axle/Gears: 3.23
80w90 or What?
I have a 91 GTA Trans AM with a posi or LSD diff, what oil should i use to replace whats in it now, 80w90 with the additive, or is it ATV or something goofy? As far as I know, everything under neath that 10-bold cover is stock, i just want to know before i blow a rear diff i dont have a replacement for.
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: 80w90 or What?
75w90 synthetic is best
If it's a real posi with friction surfaces such as clutches or cones then you always need the additive. If it's only a gov-lock LSD, you don't need the additive.
Since you'll need to pull the cover off to replace the oil, you'll be able to look inside to see exactly what kind of carrier you have.
If it's a real posi with friction surfaces such as clutches or cones then you always need the additive. If it's only a gov-lock LSD, you don't need the additive.
Since you'll need to pull the cover off to replace the oil, you'll be able to look inside to see exactly what kind of carrier you have.
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