Rear gear fluid change

[Cummins12V98]

Here is mine at 60k using the SevereGear 75-110 towing a combined 33-35k.

 

[OggyOggy]

As an FYI considering the topic, Gale Banks (Banks Power) is doing a review of various after market differential covers. Check Youtube. He isn't finished yet but it's pretty obvious from watching the testing that the after market covers touting increased fluid and cooling fins are likely doing harm to differentials. I'm probably going to get rid of my afePower rear cover and go back to stock.

 

[CMB]

I hear ya, probably selling my cover to. Leave it to Mr. Banks to spoil the fun...... in a good way.

 

[RVTRKN]

The heavier weight of oil, the hotter it will run. I went 50K on my OEM oil mostly towing at a minimum of 15K GCW. I changed to Mobil Delvac synthetic Gear oil 75W90. My diffs looked great and very little fuzz on magnet. When I get to the next oil change, I’ll know if I the Mobil worked out. But I’ve been using Mobil Delvac trans fluid in my G56 and love it.