9 1/4 and dana 44

Ok so the Dana 60 in my truck is loosing the lock it spins both rear tires for a few seconds in a mud hole then only one. Also how make a good spool for a Dana 44 for the front axle.

If I change fluid and put additive in it will if help the rear end of do the clutch's need rebuilt.

This is a first step,in the diagnosis pattern. We do not know,how YOUR truck,has been maintained(if ever..) . Don't ask,do it anyways: my recommended.