I want to drain and examine a pair of used axles I bought. Was curious if someone knows the amount of Gear Oil I need for both front and rear.
What grade?
I assume I need Friction Modifier for both.
Assuming you have a 5th Generation DT (new body style) 1500 gas motor, and not a 2500/3500, or a Ram Classic...
Page 436 in your manual (page 439 for the diesel). Under those same assumptions, no friction modifier for the front, and the rear depends on if it has the LSD or not, and what fluid you use. Some fluids have no pre-added modifier, some have not quite enough for our LSDs, and some are good without adding any more.