how often to change differential fluid?

[2001FZ1]

I'm doing an oil change this weekend and changing the transfer case fluid (97K on the Buick). How often are you guy changing diff fluid? I did the front and rear at 50k miles when I bought it.
Thanks.

 

[Mooseman]

I checked the owners manual and the repair manual and neither mentions it. The maintenance manual says to change it according to the maintenance schedule but it's not in there. So in the absence of any information, I say you should change it. It won't hurt and it's cheap insurance.

 

[Sparky]

I've been told or read somewhere every 100k for the differential gear oil. I figure I'll do mine every time I do the transfer case just to be safe. It isn't like it costs a lot.

 

[The_Roadie]

Agreed. Transfer case is every 50K, the unpublished interval for the diff is a GM goof. Many of us assume 100K. I do it every 50K or whenever I replace the axle, whichever comes first.

 

[Me007gold]

According to my owners manual 50k for severe driving conditions, 100k normal conditions

 

[2001FZ1]

Thanks guys. BTW the price for the Auto Track II went up. My wife just picked some up at the dealer, $24.57 for two bottles! Last time it was about $18.

I should have bought it from Summit...

 

[canadianbacon]

Is there a how to guide on where / how to change the differential and transfer case fluids ? would love to do it myself ...

thanks.

 

[Black_tb]

yes in the article section there should be everything you need