I was checking therearend lube level on my 03 CTD 4X4 2500 HD today and noticed it was more like 5W10 weight oil, it smells like gear lube but is very thin, even with the outside temp of about 30F. Is this right? Maybe with the limited slip diff that is the lube they use. There was some metal dust on the plug maganet but not a lot. I was checking it because I have a chatter in the back somewhere when I start out from a dead stop.
Do I have to go to the dealerand buy the Mopar brand or is there another good brand and type?

 

i use Royal Purple gear oil 75w-90

 

any 75-90 will work. . .but preferably use a good quality and stay away from the costal crap. . .I burned up the syncro's in my toyota with that **** they call oil.

no friction modifyer is needed since the LSD is a clutchless system, royal purple, amsoil, pensoil, any of your higher end oils will do good.

 

and the Royal Purple costs $2 a quart less than the Mopar oil

 

oh, one more thing. . .the lube in the axels is synthetic from the factory

 

ya, mine they recommend changing it at 20k is it the same for you guys in your rams?

 

My 2006 is scheduled to be changed out at 15,000 miles for sever usage (Schedule A) or at 120,000 miles for normal usage (Schedule B). IIRC the 1500’s and Dakotas are now required to use 75/140-gear oil and not the 75/90 the 2500 and 3500 trucks use.

 

my 07 the book says every 15000.

 

Does anyone know how many quarts the rear difftakes and how many does the fron diff takes on a 07 6.7 4x4? I'm tring to avoid the hard hitting oil/labor cost of the dealership.

 

i did my front and rear and it took 9 quarts for both.