Clunk! - Transfer Box Swap Questions


Well-known member
Good Morning Gentlemen,

I believe it is time for a new transfer box in the 90. Was hoping to consult the experts before bench pressing the thing

I have a “clunk” when I roll on or off on the throttle too harshly that is particularly annoying shifting into 3rd.

I’ve replaced my U-J’s, bushings, and A Frame ball joint. My axle diff’s seem healthy as well.

From what I’ve read on the forums it seems like this is my center differential - When I lock the center differential this “slack” seems to go away (Is my logic sound?)

It’s a 1986 90 with a discovery 200TDI, LT77 and I believe, the original 1.6 Transfer Box – I currently have it on 32” (265’s) Tires

I max out at 55mph on the highway at ~2000rpm – I’d like to replace the unit with gearing that will allow me to reach ~70mph – that being said, its already a bit laborious to get her moving in first gear.

So my questions are

1: Recommendations on gearing to suit my needs? (Maybe 1.4 box with taller 5th?)

2: Should this be a direct swap? Will I have to change gearing of anything else?

3: Best supplier and recommended upgrades? (Thinking Ashcroft)

As always - many thanks for your consideration, time and help - always a pleasure on here


Technical Excellence Contributor
Slop is often an additive thing, including the LT230. Some clunks also are caused by worn hub flanges. Before replacing anything, I’d narrow it down further, such as putting truck on stands and turning drive shafts by hand (usually twists with this “play” a noticeable amount) and see what else turns. Rear flanges can be significantly worn as well, but yeah, LT230 can introduce this play. As for gearing, if you are happy with gearing, don’t switch—match what you have. New components won’t change power! You most likely have the 1.4 ratio I believe.

as for supplier, either Ashcroft or, some folks have used Winchester Gears with better success. My new one is Ashcroft, well respected and known but some folks have gotten rebuilt that leaks. I have one in a crate for my next swap. To do again, I’d probably try Winchester due to some folks here I respect.

you can also have yours rebuilt. If in USA, most respected I believe is Rob Dassler, SW Rovers in New Mexico.
Last edited:


Well-known member
GBR also does LT230s here in the States. He's tooling up to do higher volumes of them as well.


Well-known member
Great advice so far on narrowing down the problem and also where to get a rebuilt LT230 stateside.

My $.02: I had a clunk that I would look for occasionally, but generally ignored over time and eventually ending stranding myself (and my wife) on the side of the road with no gears (AAA Premium to the rescue), running a 200Tdi and the LT77/1.6 combo at the time.

Turned out the LT77 output shaft splines were completely worn. I had no interest in rebuilding that, so I went with R380-stumpy with the taller 5th gear and a 1.4TC. Clunk is gone and much more enjoyable to drive.

Good luck!