Transfer case '04 Chevy 2500

RooferSwayze · February 25, 2019

I recently bought 2004 Silverado 2500 with 200,000 miles. The motor and trans has that "just got her broken in" feel. I was thoroughly impressed with the condition, especially after new tires and ball joints. Other than that I couldn't find anything wrong with the truck.

The transfer case went bad within a week.

The mechanic says he ordered a rebuild kit for the transfer case that belongs in the truck but when he pulled the existing transfer case he found it was for an '02 HD so he couldn't rebuild it. So he got a junk yard TC, didn't rebuild it, and slapped it in.

When I put the truck in gear (was in 4 auto) it was worse than before.

I will be getting a remanufactured transfer case put in this time around.

I can't find a forum that mentions anything along the lines of an 04 2500ld with a 02 2500hd TC.

And finally my question (sorry for the delay)

Do you think the mechanic was correct about the 02 being in there?

If so and if the part is compatible, wouldn't I want to have a HD transfer case instead?

Edited February 25, 2019 by RooferSwayze

davester · February 25, 2019

Maybe. But if it was from a '02 2500HD, then it didn't have 4-auto, just 2hi, 4hi, and 4lo, and the hd trucks didn't get the autotrak setup. There would be a round tag on the rear of the transfer case, that's stamped with the transfer case model. 2500hd's would have the NP261HD or NP263HD (1 for manual, 3 for electric shift). Don't know what the model number would be for the autotrak tc.

The np261/3HD model is stronger than the np261/263 (and whatever the autotrak tc is), but, assuming it is compatible and the guy wasn't shining you on, you lose autotrak. And I have no idea how the autotrak setup works, or how it interfaces with the trucks computers, there may be some issue there as well.

carkhz316 · March 8, 2019

To clarify a little bit further: davester you're pretty much correct. The only thing is that the NP261/63 and HD are one (two?) in the same. It's the "XHD" variants that are the ones with a slightly larger input and output shaft. Those are found behind the 8.1/ Duramax equipped trucks.

What I assume happened is this: the mechanic saw "2500" and assumed 2500HD for the transfer case rebuild (which he'd need a 261/263 kit). However, OP's truck uses the same as the 1500 transfer case, which is a NP246 (rpo option NP8 I believe).

davester · March 8, 2019

Nope, the NP261/3 and NP261/3HD have at least different components inside, even if the input and output shafts are the same (I'm not sure if they are or not). The HD at least has a heavier duty chain/sprockets, and may have other components different as well. The XHD is even heavier duty.

carkhz316 · March 8, 2019

Well, you're probably right but then they must get a little fuzzy on the details because all of the literature I've found don't elaborate on much. I would assume that the chain and sprockets are likely the only difference between the LD/HD variants. The rebuild kits and parts I've purchased don't differentiate between the HD/ non HD. Also, the last one I fixed out of a '02 2500HD 6.0 simply had "NP263" stamped on the circular tag.

I know these aren't the greatest sources (wikipedia doesn't have much beyond the model breakdown), but neither of these differentiate between the HD/ non HD

https://spprecision.com/products/np261-transfer-case-sale.html

https://www.ebay.com/itm/Transfer-Case-Rebuild-Kit-NP263-NP261-LD-HD-GM-CHEVY-GMC/181947396245?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

Edited March 8, 2019 by carkhz316