Help with 96 Silverado

[seven_magnum]

I need some help deciding differential fluid for my 96 Silverado. I have to drain my rear differential to replace the pinion pin retain bolt that I have a feeling is working its way loose. I looked around the shop and all I have is 3 quarts of Lucas synthetic 80w-90 gear oil. I know Lucas gets no love here so I'm not sure if I should put it in or buy new oil.. I would probably run it 35,000 miles before I change it. Should I run it, or buy new oil?

I thank you all for your help!

 

[Bill in Utah]

It will be fine. Use the Lucas with no worries!

Members here drink way too much koolaid. They let brands/marketing get in the way of actual common sense.

 

[SteveSRT8]

Agreed. Still way better than needed for that interval