Here is my situation:

What I have:
2 LT 230's
- one outta a 94 NAS D90 - Serial #32D321372E
- one outta a 97 NAS D90 - Serial #40D624697G and A13

Here is what I need to do:

one of the boxes has to go in a D110 pickup (you know the one that is strewn about my garage) - it is going to be a 300 tdi convert with an R380 tranny. Annnnndddddd, I am fitting a yet to be acquired Ashcroft crawler box.

So -
which box to use?
which crawler to get? (which tooth count)
will the 97 box (from a zf auto equipped D90) fit on the R-380 without mods?

Also:
I can order the crawler box from Ashcroft (through several sources - you know who you are!)

or

Source a crawler box that is new/uninstalled from a friend which is for a non-US LT230 (I think 28 tooth count gear) and the conversion intermediate gear to put in my box (not sure which it will work with). Advantages - it is in the states already and I just have to order a new one for this guy. Disadvantages - non-NAS geared box - can't have a spare box without changing its gears as well.

or

Source a crawler box from another friend that has an original pre-GKN crawler that has been never used, but is sitting in a parked truck for 2 years. Not sure of the tooth count, but surely will fit either my 94 or 97 Lt230. Advantages - its in the states and close. Disadvantages - gotta pull it off a truck, and is an older box (non-GKN though).

Anyway, sorry for the long post

Thanks for any help.

Bill R.

ps. I guess I could also get a t-case from RDS with a new ratio as well, as another option. What high ratio should I use for a 4.75 geared/38" tired/R-380/TDi for peppy around town performance, minimal highway over 65 mph, mostly offroad rockcrawler?

ps2. Will my 97 lt230 (off a ZF equipped truck) fit the R380 coming iwith the TDI? Are the output shafts of the two tranny's equal (more or less)?

Bill,

The depth of your question stupefies and mystifies me.

I will see if I can get Cooper to read your post and get in touch.

I think (but don't believe me, check!) that all the LT230s fitted to V8 90s are the 1.2 high ratio. The ones that the factory would have fitted to a TDi are a 1.4 or 1.6.

There are some options to factor into the equation then... you can reasonably easily alter the high ratio to a 1.4 or 1.6 which will shorten your road gearing in high range. This may be needed because of the V8 - > Tdi conversion and the larger tyres - I don't know if the 4.75's will make up for that - you need to do the math (http://www.autoconv.com/ratio.htm). I think the 1.2 will be too high for a TDi - are you adding a bigger intercooler etc?

If you do decide to pull the t/case apart you could also consider using the Maxidrive rock crawler cogs - a 30% drop in low range - he also makes a 40% but you have to machine some of the casting to fit them in.

Looks like a spreadsheet session coming up :flipoff2: :flipoff2:

I have a 230 question. I picked one up from someone here on the boards and from all the pic.s I have seen it looks like a 230. My questions are how do you shift it to low (that little ear on the front section?) and what input spline options are there? The one I have looks like 28 but it might be 26 but I have heard everyone say they are 10. This is not? Anyone?

Originally posted by 66CJdean
I have a 230 question. I picked one up from someone here on the boards and from all the pic.s I have seen it looks like a 230. My questions are how do you shift it to low (that little ear on the front section?) and what input spline options are there? The one I have looks like 28 but it might be 26 but I have heard everyone say they are 10. This is not? Anyone?

the 'input' shaft from the main gearbox (be it LT77,R380,LT85 etc) are all the same, and are 10 spline (i think it's 10, large coarse ones anyway)

the 'options' you can have relate to the gear ratio. the LT230 came with 1.003 1.2 1.4 and 1.6:1. the 1.2 is 28 teeth gears, 1.4 is 26 teeth and the 1.6 is 24 teeth. to see what you have, remove the round PTO cover plate and count the number of teeth you see on that gear.

to change the box into low or high ratio, there is a lever, as you look down onto the box, kind of in the middle of the box, which moves front to back. and has 3 positions (low, neutral and high) although doing it by hand is a bit hard sometimes, grab it with some pliers and turn the shafts at the same time if it won't go in easily.

Jamie

Originally posted by Jamie Austin



the 'options' you can have relate to the gear ratio. the LT230 came with 1.003 1.2 1.4 and 1.6:1. the 1.2 is 28 teeth gears, 1.4 is 26 teeth and the 1.6 is 24 teeth. to see what you have, remove the round PTO cover plate and count the number of teeth you see on that gear.


Jamie

In the US, the earlier LT230s are 24 tooth, 1.2:1 high range, the later LT230Qs are 32 tooth, 1.2:1 high range, (These are in Discos and Defenders built in the 1990s) and there are some early Range Rovers with assorted other combinations. Earlier than 1990, most Defenders are grey market and could have anything depending on what market they were originally for.

Apparently, you can change the gears to get a different tooth count without altering the ratio because the tooth counts vary but the ratios are the same on the gears that have the different counts.

Does that sorta make sense?

-John

That does make some sence. The thing I really liked about this t-case was the 1.2 high range. I run a v6 and it needs some help with 39.5's even though I run 5.13's. Thanks

Well I did some investigation and what was throwing me off was there was a spud shaft in the input gear. I pulled that out and it is 10 spline male by 24 spline female so whatever tranny uses a 24 spline output was in front of this. I see what everyone is saying about beef though because the gears in this t-case are quite large and it weighs in at 140lbs!

Humm,

Seems as though you have a grey market TF727 Lt230 with the 1.003 high range

No spud shafts on the other inputs.

Ron

To be clear it does use a 10 slpine output shaft from the tranny. One thing that is not so beefy is the 10 spline shaft is 1.160 where a 10 spline chevy is 1.375.
On this t-case I found the hi-lo lever but isn't there a dif-lock one also. There is a small one near the front output shaft but it doesn't seem to do anything when I move it but not sure yet what is going on in there.
I did mark the case and turn the input and counted what ratio it was and it does look to be 1.2 hi and 3.3 low but this was a rough measurement.

weird,

727s used a spud shaft and were only found with 1.003 high range LT230s in 83-85 RR.

Go download the manual Billnsandi posted below. it shows how the diff lock works

Post the number off the back and I can tell you what you have.

Ron

It won't be until next weekend that I am home to look at it but it did have a D in the vin# if that helps. I could be wrong about the 1.2 but it sure didn't seem to make a 1 to 1 rev. it came up short it seemed.