Forum Discussion

Explorer III

Nov 11, 2018

Differential Lube for 2016 Ram CTD 2500

As I mentioned in my other thread, I'm getting ready to change the diff lube in by 2016 Ram 2500 and would like some recommendation on gear lube.

I was looking at Mobil 1 Synthetic that meets the Ram GL-5 spec but notice it comes in 75W-90, not 75W-85 as recommended in the manual. Is this lube OK to use?

Just curious what others are using.

Also, according to the manual I do not need a friction modifier.

Update: Actually, my manual says to use 75W-85 in one section and 75W-90 in another section

I'm 2WD so I only need to do the rear diff.

Tow Vehicles

25 Replies

Learjet
Explorer
Nov 11, 2018
that is what I used Mobil 1 75w-90...no problem
ScottG
Nomad
Nov 11, 2018
I think you may also find it says to use 75/140 someplace. If you tow heavy in the heat it's a good choice.
I often tow in the desert and use it year round.
Vette_Racer
Explorer
Nov 11, 2018
I have a 3500 pulling heavy so I run 75/140 severe duty. There is not much difference in the weights you mention, go with either.
Ron3rd
Explorer III
Nov 11, 2018
Thanks Scott
What's weird is one section of my manual says to use 75W-85 and 75W-90 in another section.

Mobil 1 Synthetic OK? That's what I used in my last truck.
ScottG
Nomad
Nov 11, 2018
Yes 75-90.
No friction modifier (your diff doesn't have a clutch)