5.3 Swap, What transfer case?

nester · Post by **nester** » Mon Jul 29, 2013 4:17 pm

I'm in the planning phase of my impending 5.3 swap in my 90 GW, and I'm trying to decide what transfer case is the best for my needs and budget.

Keeping the stocker (NP229, i think, right?) Seems appealing on a number of levels, of course there's the $500-600 adapter to take into account, along with disassembling the 4L60E.

However, I see a lot of people going to other cases, and I'm curious why you chose that route?

Gumby · Post by **Gumby** » Mon Jul 29, 2013 7:53 pm

Most so far took the common "cents" approach... it is much cheaper to just swap in a transfer case from a platform that bolts up to the donor motor.

Road Trip · Post by **Road Trip** » Tue Jul 30, 2013 7:07 am

I looked at both the adapter and the Chevy T-case and opted for the Chevy T-case. I expect to have to do some driveshaft work anyway, and the Chevy NP 229 was less than the adapter, so I think I'm money ahead. Time will tell.

pcoplin · Post by **pcoplin** » Tue Jul 30, 2013 9:27 am

That's why my last two engine swaps were dodge V8s, the t-case adapter runs $500 or so. Be much cheaper to get a used Chevy case.

nester · Post by **nester** » Tue Jul 30, 2013 10:17 am

So it's primarily a cost factor?

derf · Post by **derf** » Tue Jul 30, 2013 1:58 pm

A Chevy NP241C t-case would be easiest and cheapest. No adapter needed. And the speed sensor in the tail shaft would be perfect for the computer to control the transmission. The computer needs to know when to shift the transmission and it gets that from the speed sensor. You'll have to figure out a way to tap into the speedometer output of the computer to drive a speedo on your dash but that's cheaper than adapting a non-Chevy transfer case.

If you're going to convert to a different t-case with a different low range, you're better off using a transmission adapter that puts the speed sensor in the tail shaft of the transmission. That way low range never factors in to the calculation so the transmission will always shift correctly. You can easily run any other transfer case out there at that point. A Jeep NP242 with part time and full time 4 high is a good one to run instead of the 229. In my CJ, I'm going to run a 4 speed Atlas behind my 5.3/4L60. I have the speed sensor for the transmission and I'll be getting a mechanical speedo gear in the t-case so I can have a functioning speedometer in the cab.

nester · Post by **nester** » Tue Jul 30, 2013 4:43 pm

Makes sense. I guess that's the way to go. The NP241C, they look to be pretty inexpensive too.

With regards to the linkage, what's the best route? I believe I read someone made the stock FSJ high low lever on the floor work with it? I've also seen the GM shifter added to the floor board. I'd like to be able to keep it as stock appearing inside as possible, so the stock lever is attractive to me...

ProTouring442 · Post by **ProTouring442** » Wed Jul 31, 2013 5:14 am

I'm going with the NP229 in my LY5 swap, mostly because I like the AWD capability. When I installed the engine/transmission, I basically put the transfer case back in the same place, so my linkage and drive shafts bolted up. This does limit the room in front of the engine, but I was able to solve that issue as well by moving the radiator forward.

No matter how you go, you'll need to modify a bunch of stuff anyway, so think it through and make a plan!

JeepinPete · Post by **JeepinPete** » Thu Aug 01, 2013 4:00 pm

I used the factory low range lever, sort of. I never liked it under the seat, and I wanted to reach it easier than a horizontal position would allow. So I drilled holes in the tunnel to move the whole thing forward a foot or so. Then I took a torch to the lever itself, heated it red, and twisted it so that the lever pointed up when all was said and done. I connected it to the NP241C using the NP241C factory linkage. Made it much easier to get to.

nester · Post by **nester** » Fri Aug 02, 2013 5:06 am

What years am I looking for? Seems like 90-91 have the vss, right? I'm hoping to score one from the local pull-a- part this weekend.

derf · Post by **derf** » Fri Aug 02, 2013 7:40 am

nester wrote:What years am I looking for? Seems like 90-91 have the vss, right? I'm hoping to score one from the local pull-a- part this weekend.

If you get the NP208 from an 80's Chevy you should be just fine.

nester · Post by **nester** » Fri Aug 02, 2013 2:42 pm

That doesn't have VSS though, does it?

On slightly related note, my friend has a 4L70 trans that needs a rebuild.. since I was planning on rebuilding anything I got, will it plug into my 03-04 harness?

Jeffsj · Post by **Jeffsj** » Sat Aug 03, 2013 11:40 pm

I would try to stick with the NP241c. It was easy to bolt up, though I did need to move my cross member down because of the way the t-case is clocked in the Chevy setup. You could also get a clocking ring like other members have done to rotate the case up. I believe you're right on the years you are looking for, however, it is possible to purchase a V.S.S. to attach to the mechanical speedo. output. That is what I did, because I couldn't locate a t-case that had the passenger front output AND the V.S.S. Yours should be a piece of cake with the driver's side front output.

nester · Post by **nester** » Thu Aug 08, 2013 10:01 am

Thanks Jeff...

Was just re-reading back through here.. I had read your thread as my point of reference and I just now realized that I'm driver drop. I've just done ball joints and been crawling around under it and just had ingrained in mind that the diff was on the passenger side.

LOL.

CAPTSmith · Post by **CAPTSmith** » Thu Aug 08, 2013 4:07 pm

I concur with Jeff's comments, go with the np241c. Mine matched up nicely with my 4l80e, easy to install, and linkage was a piece of cake!

nester · Post by **nester** » Thu Aug 08, 2013 7:03 pm

Found one from a 88 chevy for a good price, will just need to add a VSS through the cable. I really want to do that dakota dash, but not sure if I want to be another $600 deep into this swap.

Iroc313 · Post by **Iroc313** » Mon Mar 02, 2015 7:07 pm

Bumping this up real quick.

Do you guys run into gas tank clearance issues with the 4L60/80 swaps and new process t cases?

Post by **Stuka** » Mon Mar 02, 2015 8:03 pm

Iroc313 wrote:Bumping this up real quick.

Do you guys run into gas tank clearance issues with the 4L60/80 swaps and new process t cases?

80+ you are fine. 79 and older you may have issues as the tank is longer.

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Iroc313 · Post by **Iroc313** » Tue Mar 03, 2015 1:38 pm

Phew.

Thanks!

Post by **Stuka** » Tue Mar 03, 2015 4:06 pm

Although I should note most people that do this swap also swap in a GM fuel tank that goes in the spare tire area. That way you can use the GM pump/pickup.

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