Gear Oil Choices

[Tundra Dweller]

I’ll be changing the final drive and transmission oil.
Any reason to use something other than the 90 wt. GL5 Hypoid gear oil called out in the manual? Synthetic?

[swamper]

Use the regular heavy stuff. Synthetic makes for a lot of noise. I tried it thought my trans had gone bad, called my dealer friend and he said right away get the synthetic out and use 90wt. Hypoid, period. Noise was gone after the change back. These are very noisy to begin with. FYI- The Red Line stuff doesn't work either.

[Tundra Dweller]

Thanks Swamper. It shifts well with Dealer gear oil in it. At just under 10,000 miles it should only get better.
I'll get a couple quarts of 90 wt. Should be enough for both the tranny and final drive. Cheers!

[riceburner]

I use (IIRC) Castrol 80W90, but then I'm in the UK, it doesn't get quite as warm here.

you need 'just' over a litre, if I remember correctly, it's something like 1050ml that you need in total (1.05 litres)

[kirby]

I use 80W90 Castrol w/no additives. change once a year regardless of miles unless been riding dirt a lot then always change after return to the barn.(regardless of miles.).

:-)

[Tundra Dweller]

Thanks, I do live a few hours from Canada so no extreme heat here either.