Rear end temp

Hello all,

The following is a more complete excerpt of the aforementioned testing.
Eaton conducted tests on oil/component durability during the late 1980s early 1990s
Their intent was to maximise seal and gear life and to allow the maximum OCI possible for their Heavy Truck gearboxes and diffs when using 75w-90 and SAE50 gear oils
They found;
a) components should not be operated at consistent temperatures above 250F
b) Intermittent operations to 300F do not harm the components or oils (synthetics)
c) Oils with a sulphur/phosphorus additive package activate rapidly above 230F.
d) A poor additive package in a synthetic lubricant may not be as good as a good (thermally stable) additive package in a mineral oil.

For a more complete analysis of oils / gear testing you can read the following.
https://www.lastgreatroadtrip.com/wp-content/uploads/2010/11/gear-oil-comparison.pdf
I suggest you read all of it but Pages 19 and 20 kinda sum it up.
BTW It was commissioned by AMSOIL.

Hope this helps.
Happy Mopar:)
Arron