The Stovebolt Site Forums The Parking Lot Tons 'o Fun 90 wt oil or 80W90 in my rear axle

I'm pretty sure I've read every post on this forum about oil in the rear axle.

Here's what I gathered - if its got good seals (all new now) then I'm ok with 80W90, but otherwise I should use 90wt (Pure 90 - I'm guessing its more viscous?)

The post that I read that concerned me mentioned that heavier duty trucks should use the heavier oil. Mines a 1 ton - what do the other 1-tons guys use?