Diff fluid change interval/lube

[Pit Bull]

Background - 02 Dodge 3500 CTD 4x4 ETH/DEE, daily driver 45 miles round trip mostly highway. Driven 18,000 miles per year very limited light towing or hauling. Climate is SW Missouri not very cold or hot. How often should I change the lube in my diffs? What lube should I use?

 

[cousincletus]

Check your owners manual, but I'm pretty sure your truck calls for 80W-140. I have a Dodge 1500 and use 75W-90 Series 2000 Amsoil Synthetic. Once you switch to synthetic, you don't have to change it again unless it gets water contaminated, etc. I work for a trucking company, and the mechanic said that they don't change the synthetic oil in truck rearends, either.

 

[RichR]

Hi Pit Bull,
Do you have a LSD?
On my last truck with out the lube stayed clean for 20-30k.This one has a LSD and I change yearly to get out contaminates.But then I am over the top on my lube intervals since I started hanging out here

RichR

 

[Dominic]

I personally like to change my lube in drivetrain parts every 30K, even though its usually clean. It doesn't cost me much and its not like I change it that often anyways

 

[timzak]

Ford recommends flushing the diff on my Mustang every 100,000 miles. I did mine at around 90K. They recommend 80W-90 and 4 oz of friction modifier. I used Durablend 80W-90 (synthetic blend) and the friction modifier. I probably won't have to change it again unless I keep the car another 9 years.

 

[mikeinaustin]

I agree with Dominic, change every 30K, very inexpensive insurance against failure.