Has anyone rebuilt an LT230 transfer case?

Jeff Blake

Well-known member
May 6, 2016
429
16
Pacific Beach, San Diego
Jeff, it would be awesome if you made a write-up with pictures (besides the YouTube video) and posted it here.

Happily!

Here's part 2, completing the teardown: https://www.youtube.com/watch?v=jFrzAJ0XvGU&feature=youtu.be

Next up, inspection of components and an overview of the new components I'll be fitting (high range gear, intermediate gear cluster, input gear, and of course all new bearings, races and seals)
 

Jeff Blake

Well-known member
May 6, 2016
429
16
Pacific Beach, San Diego
Kicking this project back up again... cleaned some parts today, lots more to clean tomorrow. Hopefully will get the rebuild under way shortly. Really looking forward to 1.41 gears and CDL

Weapons of choice:

CRC gasket remover (this stuff is gold)
Engine degrease aerosol
brake cleaner
Plastic chisel, plastic razor scraper, brass brushes, plastic worm brushes for bolt holes, etc

Tedious, time consuming work.

Don't use simple green or purple power, it seems to do weird things to aluminum.

And of course the rover lent a hand with onboard hot pressurized water
 

Jeff Blake

Well-known member
May 6, 2016
429
16
Pacific Beach, San Diego
What is normal play on the hi-lo selector hub fitted to the dog teeth of the low or high gear? When fitted, I'm getting about 2-3mm of rotational play on a brand new high-gear. And 1mm of side to side play. It also has a small chip on the outer sleeve

Ashcroft sells new hi/lo hubs for about $120 shipped, which is a lot, but everywhere else the cheapest I can find is like $400+
 

Jeff Blake

Well-known member
May 6, 2016
429
16
Pacific Beach, San Diego
Crickets in here haha

Basically done with the rebuild. Just need to get a CDL shifter so I can use the brackets and mount the hi-low and diff lock housing.

I spent quite a bit of time experimenting with the diff lock engagement. I found one big concern...

- The front switch with only one washer was causing the dog clutch to get intermittently stuck open and/or locked, and even worse it would get "partially locked", i.e. diffs are locked, but the clutch was only ~25% engaged onto the front output shaft. There is no actual part number for the washer (??), and the manual says to "caution: ensure washer is same thickness as original." Well my case didn't have switches so I couldn't compare. The switches for the hi-low and neutral detect are the same design, so I used that washer. I ended up doubling up on washers for the front switch as you can see in this video:

Diff lock demonstration:
https://www.youtube.com/watch?v=V1HR5ff7QNQ

I'm still worried that if I engage diff lock, and the lamps go on, but the dog clutch is only partially engaged, leading to possible damage. There's no way to know if the diff lock is fully engaged without pulling the side cover and looking at the selector fork.

Paging anyone who can shed some light on that...

Some more notes...
- with diff lock switched on, you are not necessarily in diff lock yet. The lever only pulls the spring. So if the dog clutch isn't lined up with the output shaft, you won't be locked yet. I noticed that the center diff gears need to rotate a bit sometimes in order for the spring to find the teeth and move the fork over. In practical terms, you need to steer the car left or right a bit in order to work the center diff gears. Driving straight won't work like it does for the hi-low.

edit - correction - my case from Will had all the switches, but NONE of them worked. Imagine the odds...? 2 diff lock switches, neutral switch, and hi-low switch. Latter two being very expensive little buggers :(
 

Agent

Well-known member
Jun 20, 2007
669
3
WV
Excellent and informative posts! Thanks for taking the time to post it up for us all to learn from.
 

Jeff Blake

Well-known member
May 6, 2016
429
16
Pacific Beach, San Diego
Sorry guys I stopped making the videos and tutorials... but good news is I finished the rebuild and installed it over the past few days. Great to see that diff lock light after a year spent on and off rebuilding with 1.41 gears, new bearings, and HD cross pin

Happy to answer any questions about the process
 

WaltNYC

Well-known member
Mar 3, 2010
707
135
NYC
I subscribed to this thread as it is basically a reference manual now. Thanks to Jeff for following up on the completion. Happy trails!
 

Jeff Blake

Well-known member
May 6, 2016
429
16
Pacific Beach, San Diego
Jeff, any updates?

Yes I finished the rebuild last summer, it's been in the truck now for ~5,000 miles, no issues, working great. Just did about 1,500 miles last week to Big Sur and Tahoe. Changed the oil a couple months ago and looks good, so hopefully I'm in the clear. Not leaking either, the Permatex anaerobic red stuff seemed to do the trick.

With CDL, front/rear locked, and 35s now, she's a completely different truck! Sorry no more video or install details, I got lazy on that.

I didn't end up doing the ATB. I put in an HD cross pin and 1.4 gears from Ashcroft, and of course, CDL. And new timken bearings

Didn't really notice any difference going up hills with the 1.4's in. It got a little better with 4.12's and 35s, but its still a bit of a dog up hills (like climbing to Tahoe)

Overall it was a little more challenging than rebuilding the engine, mainly due to the special tools (you really need a couple LR tools plus dial indicator base to do it by the book) and precision needed to get the preloads all correct. You could probably do it by feel though and get away with it

With all 3 diffs locked I'm not sure what real benefit an ATB would be. An underdrive, on the other hand...
 
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Batrover

Member
Jan 17, 2016
11
2
Houston
Hi Jeff: I’m having some issues with my 04 D2 diff lock. When I lock it, I can see through the switch hole that the selector spring isn’t visible: the selector isn’t sliding into locked position. Is it possible to pull the inspection plate while installed on the truck? Looks as if one bolt could be too long to remove—potentially hitting transmission.