I am very new to this but today I checked the differential fluids in the front and rear diff of my 2001 2500 4X4. The front was kind of a clear/aqua color and the rear was more like rust/oily. Any thoughts? Is this normal or did someone put different fluid in each? I have had this truck for one year, it has 130,000 miles.

Thanks.

 

Front and rear could have different brand name oil and viscosity.

Front will stay clean for a much longer time than the rear unless you are in 4 wheel most of the time.

Rear if it is just a amber/rusty color must have been changed not too long ago.

 

thanks Aaron, I appreciate it. Was worried that there was something wrong even though I had no symptoms.

 

The AMSOIL synthetic I filled my rear diff with last change was a real pretty blue.

The Dino stuff I used before was an amber color.

 

which synthetic is good to use on the rear end? I'm gonna change it soon.

 

I like Royal Purple 75w-90 http://www.royalpurple.com/prodsa/mgeara.html
Since you live in the north unless you tow I wouldn't use any of the 140w multivis oils, too sluggish when cold.
Use the dealer locator to find where to buy less than case quantities or buy online.