2013 Tahoe diff oil recommendations?

[K20FA5]

I posted on here a while back in an old thread an email directly from Eaton. They told me that they don’t recommend any friction modifiers in the G80 locker. There are a lot of people who use it anyway, and who knows if it really makes a difference or not? Eaton said not to use it, so I don’t.

 

[tyman]

I posted on here a while back in an old thread an email directly from Eaton. They told me that they don’t recommend any friction modifiers in the G80 locker. There are a lot of people who use it anyway, and who knows if it really makes a difference or not? Eaton said not to use it, so I don’t.

Yup. Nothing with “extra FM.”

 

[repairman54]

M1 uses the LS in the description for limited slip applications
I've never used a modifier lube in any of the many G80's I've had.

 

[dan_erickson]

I did a drain and fill with Redline 75w90 on the front and rear diff. Someone must have changed the rear diff fluid at some point because it was not to bad looking. The front was straight black and nasty.

 

[Dino01]

I did a drain and fill with Redline 75w90 on the front and rear diff. Someone must have changed the rear diff fluid at some point because it was not to bad looking. The front was straight black and nasty.

That’s pretty common in a lot of rigs, the Tundra in my sig gets both changed at the same intervals, but the front always looks worse, probably due to getting minimal use at operating temperature and a tiny bit of moisture finding its way in due to location, but i could be wrong in that

 

[350Rocket]

That’s pretty common in a lot of rigs, the Tundra in my sig gets both changed at the same intervals, but the front always looks worse, probably due to getting minimal use at operating temperature and a tiny bit of moisture finding its way in due to location, but i could be wrong in that

I remember the same thing when I was doing oil changes in a Pennzoil express lube. Ford was the worst, looked like they were full of water on basically every f150 but I believe they all looked worse in the front.