Rear & Front Axle Capacity
 

How much fluid do they hold? Dealer said 4L (10 qt.) for the rear and 2L (4.5 qt.) for the front. Can't be that much, can it?

What axles do you have. You really need to fill out the signature o we can see what your workin on. Even in the same years they can come with different axles depending on how they are equipped.

Like Uncle B said, you have options. Here's the list:
Differential, 9.25 AA Front..........4.6 pints
Differential, 9.25 AA EL Front..........4.2 pints
Differential, C205FD Front..........3.4 pints
Differential, 10.5 AA Rear..........5.3 pints
Differential, 10.5 AA EL Rear..........5.3 pints
Differential, 11.5 AA Open Rear..........8.9 pints
Differential, 11.5 AA Trac-Rite Rear..........8.4 pints
Differential, 248RBI (DANA 60) Rear..........5.9 pints[10]
Differential, 9.25 Rear..........4.4 pints[

he has the 9.25 front and the 11.5 rear, only axles available with a cummins in those years........

In my 06 It took just over 7 qt's to refill both diff's, but I also pulled the cover and let them drain.

I just did mine over the weekend, and the stock front took 4 quarts and the rear with my Mag/Hytec pan took about 6-6.5 quarts.

I have finished a front differential oil change and I was trying to put the 4.3 quarts and I could bearly put 4 quarts .I think got in there like 3 Qt and 30 Oz ,Is that enough or is there another way to put in the extra 5 oz

Don't worry about the amount! Just fill it till it comes out the fill hole and your done!

He is right. I have seen several 'lists' that are wrong about capacity. Usually it is way off for an auto trans too!
I caught every bit that came out of the rear and it was exactly 4 qts. I put the Mag Hi-Tech cover on and it took exactly 8 qts. to fill it back up!! The cover is deeper (Hits my spare tire when hauling!) and the level is now higher than OEM! (I didn't get to do the front. Dealer I bought it from tried to 'nuke' my axle when they changed the pinion seal :argh:. So another dealer changed the fluid when they replaced the bearings.)