Rear Differential 87 k5 blazer Silverado 5.7 tbi 350

[K5Blazerboy87]

Hi guys I changed my rear end fluid put on a new gasket and stuff that has form gasket or something like that idk but anyways I put in 2 quarts of 80W-90 is this enough gear oil or do I need to add more? If so how much more

 

[Rusty Nail]

Add until it begins to come out of the hole. You cannot overfill, only underfill.
I think it's closer to 4 quarts?

If you have G80 positrac, make sure the additive is in the fluid you use.

 

[K5Blazerboy87]

No its just the simple O'Reillys masterpro 80W-90 gear oil ok I will go up tomarrow buy 2 more quarts