Hello everybody I am new to the form. I just bought a 2003 blazer and it has the g80 RPO code which I read needs limited slip fluid. I have to do a rear bearing and I want to do a drain and refill on the front and want to know what fluid I need to use or what additive I need to get and in what ratio. I'm in Canada so if anybody is from Canada on here and they know of something from Canadian Tire or something like that let me know any help is appreciated. Thank you

 

Just use plain old 80W90 with no additives. Either dino or synthetic, your choice. The additives eat up the clutch pads in the G80 Gov-Loc.

 

So motomaster 80w90 extreme pressure gear oil would work ?

 

Not familiar with that brand. I use Valvoline regular 80W90 gear oil

 

this stuff ?

 

Sorry I didn't see this sooner! Southern Ontario here...

I grabbed motormaster 80w90 to do my fluid change without an issue. I'll be getting more when I do my axle swap.

What area are you from?

 

I just now looked at my records. Here is what I have been using:
Valvoline 80W-90 gear oil; p/n: 773732 (old p/n: VV832)
rear cap. = 4.0 pts
front cap. = 2.6 pts

Edit:
FYI: As for part numbers: the 773732 is for when it comes in the gallon container and VV831 is for when it comes in the quart container.
https://www.valvoline.com/our-produc...mance-gear-oil

 

No limited slip additive needed in a gov-lock G80 gear like these. Gov lock is not limited slip.