75w140 vs 85w140 for Dana 30/35

[leojeeper]

According to the sticky thread here, the Dana 30/35 require 75W140 gear oil. Looking online and locally I’ve found 85W140 significantly cheaper. The 85W140 is also easier to come by around here. Is there a significant difference between the two? Can I use 85W140?

 

[MountaineerTom]

You should be ok. The 85w-140 will be slightly thicker.

I run 85w-140 in my front Dana 30 (mainly to help quiet down the auto locker I have in it) and the rear Dana 44 with no issues.

 

[leojeeper]

You should be ok. The 85w-140 will be slightly thicker.

I run 85w-140 in my front Dana 30 (mainly to help quiet down the auto locker I have in it) and the rear Dana 44 with no issues.

Thanks, that’s kinda what I was thinking. If I can get the 75W at the time I go to get it I’ll get it, but nice to have a backup option.

 

[Jerry Bransford]

The axles aren't particularly fussy about their viscosity except perhaps at extremely cold or hot temperatures.

 

[leojeeper]

The axles aren't particularly fussy about their viscosity except perhaps at extremely cold or hot temperatures.

Thanks Jerry

 

[leojeeper]

The axles aren't particularly fussy about their viscosity except perhaps at extremely cold or hot temperatures.

I have a quick follow up, I found a manual online and says 80w90 with 75w140 for towing. Is my thinking right that I’d be better off going with the 75(85)w140 if I’m going to be off roading?

Thanks

 

[Rickyd]

I have a quick follow up, I found a manual online and says 80w90 with 75w140 for towing. Is my thinking right that I’d be better off going with the 75(85)w140 if I’m going to be off roading?

Thanks

If your offroading is highway speeds with high loads like when towing then yes. If not then no.

If you have a tow hitch use the thicker oil to be safe. If not then put whatever is handy in it