Stop in for a cup of coffee
Gear Oil, Synthetic Mobile 1 LS 75W-90 1 qt 22 oz.
Limited slip Clutch additive ATP AT-210 4oz.
Long story short. No reason to go heavier unless generating lots of heat.
A little less on the cold rating will help in colder weather.
I don't think your in danger of breaking the axles, but the former head mechanic at Pheonix had a story about doing that at his first job. Apparently got to be real gentle getting things moving with an early Powerwagon's drivetrain in super cold weather and old time lubes.
This what I ended up with for the 8.75 with Dana
Gear Oil, Synthetic Mobile 1 LS 75W-90 1 qt 22 oz.
Limited slip Clutch additive ATP AT-210 4oz.
Long story short. No reason to go heavier unless generating lots of heat.
A little less on the cold rating will help in colder weather.
I don't think your in danger of breaking the axles, but the former head mechanic at Pheonix had a story about doing that at his first job. Apparently got to be real gentle getting things moving with an early Powerwagon's drivetrain in super cold weather and old time lubes.