I need to change the fluid in the front and rear differential of my 2006 ram 2500 with cummins 5.9l. Is dropping the covers off and reinstalling the easiest way to do it and what is the capacity of each. My owners manual does not indicate how much. Also how often should it be done. I tow a 5th wheel.
Thanks

 

A little under 3 qts in the front and a little under 4 in the rear, using a synthetic 75w-90, (no limited slip additive is required if you have that type of rear axle). The manual recommends 30k as normal, and 15k as severe intervals.. But most guys on here have found that at 30k the fluid is still pretty new looking. I doubt going longer would hurt. I've got about 50k on the fluid I put in at 15k.

 

I agree with the above but I would also wash off the diff first with water if you do any off road driving in mud or dirt, you can also take a stiff brizzle brush and clean top of housing really well first. If you don't the dirt will fall into diff when removing the cover. Removing any dirt that may fall into diff and onto the gears can be very tedious job. A word to the wise. Also donot spray any brake clean on gears or bearings.

 

The rear diff has a drain plug, no need to take the cover off and the front diff has no gasket, so you can just crack it loose, drain and re-fill. I wouldn't bother with taking the covers off unless you suspect other problems or see alot of metal coming out in the fluid and think it needs cleaned up.
7qts will get both axles.

 

The factory rear and front covers are equipped with fill plugs, serving as a means to fill the differential. Removing the plugs will not drain the fluid. They each have gaskets that are reusable.

I agree with the recommendations made by BigIron70 and 92'1stGen.

 

I went the easy route...replaced both covers with PML (front) and MagHytec (rear).

The drain plugs make it super-easy to drain the fluid. Plus capacity is greatly increased.

Of the two, the Mag Hytec cover is the higher-quality piece.
It's got o-rings and a magnetic dipstick, plus a better finish.