15 years, 50 Thousand miles on my rear diff, transfer case, and front diff fluids. Time for a service?

[c good]

Didn't realize it was that long since I've owned my Envoy. Do the differential and transfer case fluids degrade like engine oil over time? If so, I'm in trouble! I only have 50K miles on all the fluids since I serviced it in 2009. Top notch Mobil One full synthetic in the differentials. Auto Trac II GM fluid in the transfer case.

Is it time? Thanks for any input all. Cam

 

[flyboy2610]

It probably wouldn't hurt.

 

[xavierny25]

If it's been 50k miles transfer case is definitely dew for a change.

The differentials and transmission I top off if necessary when I change the transfer case fluid.
I also drop the pan and change the filter on the transmission every 80K miles. The diffs get fresh fluid every 80k aswell. I've got 265k miles on my 08 Voy original drive line except for the rear diff that I just swapped out for the beefier 4.10's from a 08 TB SS. Nothing really wrong with the old 3.42 rear just started leaking from the driver side seal again. I replaced the seals and bearing on it over 5yrs ago.

Here is a good thread

https://gmtnation.com/forums/threads/drivetrain-fluids-specifications.193/

 

[Mooseman]

Like the man used to say, you can pay a little now or a lot later. Transfer case definitely due as per manual and past experiences here. Diffs not a bad idea. Tranny, look at it this way, I change mine every 50k KM. It's cheaper than a rebuild.

 

[Mooseman]

And another thing, oils also break down by AGE, not just usage.

 

[c good]

Like the man used to say, you can pay a little now or a lot later. Transfer case definitely due as per manual and past experiences here. Diffs not a bad idea. Tranny, look at it this way, I change mine every 50k KM. It's cheaper than a rebuild.

I service transmission at 30 K miles. Fluid and filter. I'm good there. Was just wondering about the diff's and the transfer case. I'll be doing those this next weekend.