Rear Axle Maintenance

[Tumbleweed]

Hello All;
I have a 2018 Ram 2500 4wd with a 3.73:1 limited slip rear axle. I believe it is time to change the rear diff fluid.
Coming up on 60,000 miles.
What fluid weight is required and are any friction modifiers required?
I've searched the forums and couldn't find the answer I'm looking for.
Thanks in advance.

 

[Tom Davis]

Owners Manual will have all the information you need as far as fluid and additives go.

 

[JW2 Innovations]

Here's screen shot from my owners manual from 2016 2500



Source LINK

 

[rzr6-4]

Here's screen shot from my owners manual from 2016 2500

Interesting, mine is 09 2500 and they say 75-90 for light duty or 75-140 for HD application. Looks like they changed it to 75-90 for everyone. Wonder why.

 

[JW2 Innovations]

Interesting, mine is 09 2500 and they say 75-90 for light duty or 75-140 for HD application. Looks like they changed it to 75-90 for everyone. Wonder why.

Not sure, my 2006 F250 was as you list with different weights in front/back. Same in fact.

Edit: I miss read I think, you're saying if HD then go with 75-140. Ford I mentioned was diff between front/back

 

[Tumbleweed]

Thank you all for your help.
I do not have a paper owners manual, but did find the .pdf file of it.
It is as you, JW2 Innovations, stated.
Funny how the page count is different in my manual.

 

[Tumbleweed]

Actually, mine asks for 75w-85 GL-5 Synthetic not 75w-90 GL-5.

The specs are always changing.

 

[JW2 Innovations]

So here's a weird one:

I posted above an image from 2016 Owners Manual for 1500/2500/3500 located here - (for 75W-90): LINK

Later, I pulled my manual from the truck, and it says 75W-85 - Yep, no kidding! LINK for PDF version of that.

 

[Tumbleweed]

And the specs have probably changed since the .pdf was made!!!

 

[JW2 Innovations]

Page numbers you mentioned before too....between the second LINK and my paper copy....off by 4 pages as well. I'm wondering if there are versions of print or something. Put in another warning earlier in the book and page numbers get pushed back.

 

[Edward Hands]

 

[Edward Hands]

 

[Edward Hands]

 

[Dusty]

Interesting, mine is 09 2500 and they say 75-90 for light duty or 75-140 for HD application. Looks like they changed it to 75-90 for everyone. Wonder why.

Just a guess, but like the switch to lighter engine oils, reducing the viscosity range of gear oils will likely reduce drag.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 113441 miles.

 

[nascar72]

Interesting, mine is 09 2500 and they say 75-90 for light duty or 75-140 for HD application. Looks like they changed it to 75-90 for everyone. Wonder why.

The screen shot shows same thing for my '08 2500 wich is 75w90 and no additives needed. The 75w140 is for the 1500s.

 

[Trailmaker]

75-90w
We have discussed it here.

Change your rear diff oil if you haven't yet and clean those lockers!

I did everything front rear trans and transfer at 10 k as its break in as I did with the engine the day I picked it up

www.ramforum.com