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My 2000 AWD to Manual NP233 4x4 Upgrade!

33278 Views 134 Replies 28 Participants Last post by  Beaver's guts garage
Well, well... it's finally my turn to do this upgrade!

I keep finding myself working on job-sites pulling heavy loads off-road desperately needing 4-LO range gearing and full time 4x4 operation. The 4.3 in the single high range AWD with taller tires and stock gears just isn't working well for me at all... it generates a lot of sudden heat... it struggles badly and is severely under-powered... and it REALLY puts a strain on the trans too. The AWD system has reliability and operational issues too, issues with sticking or failing encoder motors (99-up), issues with clutch-packs and wear, but most importantly lacks a very needed low-range gear.

I considered both the NP233 vs the 236 transfer cases... but since I do not live in snow country, I do not need the benefit of the auto AWD, or the complexities of the 236 installation. The simple drop-in NP233C was chosen!

I have also chosen to go with the "manual" shift conversion vs the electronic push-button shift, for both simplicity, dependability, and reliability.

I'm re-posting a couple of posts (from a couple different threads) so I have it all here in my build thread. This was the start topic...
NP233 vs NP236: ... 9&t=135734


July 5, 2018:

UPDATE: My "new" 233 unit arrived today! :mrgreen:
Actual unit weighs only 68lbs... much lighter than I expected.

I purchased the unit though Ebay, $175 (including shipping)
This unit is from an 03 Blazer. I confirmed it has 32-spline output.

I've read there may be some case indexing issues old vs new.. I'l let you know how this one does.

The unit is light enough it can be lifted and carried with one hand.
I turned everything by hand and verified the 4x4 Hi/Lo selector is working.

The new basic gasket/seal kit arrived today as well... $12 on Amazon.

Now to fabricate my manual shifter.

I'm learning toward possibly something similar to this that "LiftedAWDAstro" did on the other site... but perhaps either a little shorter, or further back.
I will experiment with leverage lengths and angles once the cable is in place.
I have a box that sits in the center between the seats, so this really won't be visible.

Looks like I may go with this Lokar S-7100 cable kit ($50 from Summit) connected to a simple shifter mounted to the side of the driver seat facing forward. I think I'd prefer the shifter close as possible to the seat vs cutting open the floor.

This cable kit appears to have everything I'll need (except actual shifter lever)

But I'll probably take a visit to the junk yard just to see my other options.
I'm pretty excited about taking this to the next level! :D

See more at NP233 vs NP236: ... 9&t=135734

July 7, 2018:

The new unit is here.. I'm just shopping for my best linkage solution. Still undecided on the Jeep Liberty shifter (found a nice one in JY yesterday).. or making my own (shifter mounted on the side of the seat base). The Liberty shifter will be the simpler and cheaper choice, and comes complete with everything I'll need. I'm probably going to go back and pull it Monday, regardless. The cable though the floor to a simple seat mounted shifter is my preferred choice. But once I cut the big opening in the floor, the choice will be made.
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Awsome write up. Can't wait for the rest of it.I'll be following along about 2 weeks behind you only on a '96. Journeys off road says I'll need two new driveshafts also.
Thanks Mmusicman for getting this going. It's really great to see everyone jump in with all the options! I was going down a rabbit hole wondering how to "plumb" in the shifter for my 233C. I wasn't aware so many have already done it. Thanks to everyone for the contributions.l :bow:
Maybe some extra treats. If it was a dog he'd of slobbered all over ya while down there!
I've never owned a 4x4, so if I sound like a dummy, well I am. The shifting video looks like only 3 positions. Aren't there 4? 4 lo, 4 hi, Neutral and 2 hi.?
I'm going with the change over since there are no rebuild parts for the BW4472. And I've got a clunking from it.
I'm getting everything together to do this project. Found out I had wrong drive shaft and none of the local yards have an AWD of 1999 or later. So off to flea bay. I found one that says it is 31 spline. Can they just not count very well or is there really a 31 spline and a 32 spline for these vans?
1 - 8 of 135 Posts