2002 vs 2003 Dana 44 rear axle parts differences

[nondem]

Fortunately I got the year model of the TJ my donor Dana 44 came from. It's a 2002 and my Jeep is a 2003. Both don't have antilock brakes.
Can someone tell me why the parts breakpoint for some of the Dana 44 axle parts are between those two year models? For example - I'm looking at a bearing kit that fits 96-02 models. What changed in 03? Is it just the potential for having antilock brakes?
I was happy to find an axle with only a single year-model difference but I guess that's not close enough for some things

 

[nondem]

Jeep Wrangler TJ 2003-06 Dana 44 Thick Rear 3.73-5.13 Ratio Koyo Bearing Gear Package Revolution Gear​

Jeep Wrangler TJ 1996-02 Dana 44 Thick Rear 3.73-5.13 Ratio Koyo Bearing Gear Package Revolution Gear​

Here is an example from Revolution gear's site. There is obviously something that changed...and it doesn't appear to only be the availability of disk brakes.

My front(Dana 30)is a 2003 like the rest of the Jeep but I'm trying to incorporate this 2002 Dana 44. I guess I can buy gears separately as long as they are the same ratio but I'm curious what the deal is?

I noticed looking at lockers there is mention of the "HD" version of the Dana 44...wasn't aware of that either

Anyone have an idea or any thoughts?

 

[jjvw]

@hosejockey61 , do you pay any attention to what year TJ your junkyard D44s are from when you rebuild and regear them?

 

[machoheadgames]

97-02 shimmed under the carrier bearings with stacks of a few thin shims. 03-06 used thick correct-width shims outside the carrier bearings. Best to stick to the shim type for the axle you are building due to fitment. I’m not sure if the shims are why they list them differently, but that is probably why. I am not aware of any actual gear differences at all.

Also different ring gear bolts. 3/8” on 97-02 and 7/16” on 03-06. The carrier itself is different due to the bolt holes but it also might be dimensionally different due to the different shim types. Not sure on that, would need to be confirmed.

I’m not aware of any other details that really matter, but that doesn’t mean I’m not missing something either.

 

[hosejockey61]

@hosejockey61 , do you pay any attention to what year TJ your junkyard D44s are from when you rebuild and regear them?

The pinion seals can be different, but as far as gears go, they're the same. Maybe some minor differences as listed above but that doesn't change anything for me personally.

I'm not sure about the anti lock brake differences. Bearings are the same for sure though.

 

[nondem]

@hosejockey61 , do you pay any attention to what year TJ your junkyard D44s are from when you rebuild and regear them?

Yes, it was a 2002 Jeep that this Dana 44 came from.

 

[nondem]

Thanks a lot guys for the responses. I happened to watch(and like) the videos BFH did on pressing bearings on the shafts and gear swaps on the Dana 44 axles etc...very informative. I've only ever handled axles that had C-clips and the seals just tap in on the housing. The Dana 44 is sure different.