lxcoupe

iTrader: (9)

Hey all, I have a chance to purchase a 4L80E/ transfer case out of a 2004 Suburban with 100,000 miles. Seller states:

"Np246 32 spline transfer case"

I have push button 4wd (I don't see "auto" on the dash so I don't think it's Autotrack) in my recently acquired 2005 RCSB Z71 and I am planning a 4L80E swap. I definitely want to keep the push button 4wd.

Any thoughts on picking up this used trans/ transfer case and throwing a Transgo shift kit in? My goal is 4wd launches, 550rwhp and mid to high 11s.

thunder550

iTrader: (70)

246 is not from a 2500HD. The 2500HD has either the 261 manual shift or 263 electric shift t-case. 246 is the standard Autotrac tcase from the half ton trucks and SUVs.

I'd keep the one that's on your truck already, should just be able to swap the input shaft and bolt it up to the 80E.

lxcoupe

iTrader: (9)

Ok I was mistaken, I read it wrong, the seller actually has a NP263 that is still bolted to the 4L80E and it's from a 2004 4x4 2500 Suburban.

Would you still recommend just swapping the input shaft on the existing transfer case?

thunder550

iTrader: (70)

Ah ok that makes more sense. In that case I'd run the 263 as long as the electrical stuff works out. I'm assuming it will since you're going from electric non-autotrac to electric non-autotrac....

lxcoupe

iTrader: (9)

I wonder how much power the NP263 robs compared to the NV246?

thunder550

iTrader: (70)

I doubt there's much of a difference.

lxcoupe

iTrader: (9)

I think I've decided just to change the input shaft on the NV246. I can't find a single person who has used the 2500HD transfer case.

thunder550

iTrader: (70)

I read somewhere today that the motor for the two cases is the same. If it is, it would be cheaper to use the 263 than to have to buy the input shaft and easier than opening the tcase up to swap them. Although, either way I'd recommend installing a pump rub kit so the oil pump doesn't wear through the case.

Strength wise though, either one should be fine.

thunder550

iTrader: (70)

What's the RPO code for your existing tcase?

lxcoupe

iTrader: (9)

Transfer case code on my build sheet says ZB. Is that right? 05 Silverado RCSB Z71, push button 4wd.

Unfortunately, I missed out on the transfer case. Since I didn't jump on it, the guy promised it to another buyer. I helped him separate the transfer case from the trans, then the trans from the motor (it was actually an 8.1L truck). I'm not too disappointed since the trans is mint and I looked at the tag on his transfer case and it said "246" so I'm fairly certain it's the exact same transfer case as the one I currently have, except it already has the 32 spline input shaft. It would have been nice not to have to swap the input shaft over though. Paid $500 for the trans, he wanted $300 for the transfer case.