22D Transfer Case

[DieselBoy]

Currently I have a Disco 1 28D 1.222 ratio transfer case coupled to my R380 gearbox in my 1997 300tdi.

It was fitted before I got her, and I have put up with it for a few years. As I am based in NZ, we don't have any long flat roads, and I am running 255 85 16 tyres so I really want to correct gear ratio's.

I have just sourced a 22D 1.410 ratio LT230 from a 1989 90.

So what do i need to be aware of to do this swap sucessfully??

I realise my handbrake will need swapping over, and there will be some messing around with input gears??

Its the input side of it I am trying to work out.

According to the Ashcroft site, in my current set up should have the 26 tooth, cross drilled, 135mm input gear.

Is it a straight swap of shafts from the 28D into 22D??

So if I'm putting a Early 1989 LT230 (don't know what the suffix is as I haven't picked it up yet) onto an R380, what input gear do I need??

[DieselBoy]

Right, so the T.Case number is 22D 020960 B, and it's going to be mated to a R380.

What input gear should I be using for this combo??

Cheers,
Pete.

[DieselBoy]

Interesting, its all bloody hard to make sense of!!!

You read one web site and it says that the suffix B t.case has a different profile gear to the C suffix case, so the revised cross drilled gear doesn't work. Ashcroft site says suffix A & B can't take the upgraded gear also.

Then there's this Land Rover service bulletin that says the revised cross drilled gear fits everything
Service bulletin
http://www.geoffrey-miller.demon.co.uk/rrr/transfer/41_06_95_en.pdf

Yet on the Ashcroft site it clearly states cross drilled is not available
Ashcroft Transmissions - Input gear (http://www.ashcroft-transmissions.co.uk/index.php?act=viewProd&productId=8)

I was getting my info from here:
Geoffrey Miller's website (http://www.geoffrey-miller.demon.co.uk/rrr/transfer/)

Looking through some parts list documents, it seems the FTC5089 gear replaces the FRC8917. The FRC8917 was the gear used in the Suffix C cases. No mention of the FTC5089 replacing the FRC5428 gear in the Suffix B case.

So from that, what I can gather on the Ashcroft site, and what the Geof Miller site said about the gear profiles, what ever gears already in it, is what it needs. So I get a new FRC5428 and get that drilled.

I think...........

Can anyone confirm???

[ashtrans]

the A and B will need FRC5428, you can either drill it but its not easy or fit it with an oil feed plate :

Ashcroft Transmissions - oil feed plate (http://www.ashcroft-transmissions.co.uk/index.php?act=viewProd&productId=208)

Dave

[DieselBoy]

I have ordered the new gear, cheers for the confirmation :)

I suspect I can get a local engineering company to do the drilling for me with out to much bother.

What do you think is the best solution though, oil feed plate or cross drilling if I can get it done??

Cheers.

[Jode]

Presumably the cross-drilled gear provides better oil bathing than the feed plate, otherwise LR would simply have used the feed plate as standard thereafter and not bothered with the cross-drilled gear. I would have thought that the gear has been hardened after machining and may prove hard to drill.

[wrinklearthur]

A couple of things;

The gear can be drilled with a ceramic masonry bit that has been reground to suit hardened steel.

How is it that some early transfer boxes don't have trouble with the top gear and others wear badly, isn't it constant speed on the open road that carries oil
up to the spline of the top gear ?
.