LT230 revisions

[shack]

Does anybody know what revision of LT230 wouldn't have a High/low switch, and more specifically what it would be fitted to?

[DazzaTD5]

As far as I know there is no version of the LT230 transfer case that didnt have a hi/lo switch (which is the horizontal mounted switch)

BUT if you mean the hi/lo detent switch on the TOP of the transfer case then...
U.S models Discovery 2 had this detent switch, other markets didnt.
Plenty of last model Discovery 2 had this switch but it wasn't connected. (I suspect a surplus of transfer cases).
Defender TD5 and TDCi had this allowance in the casting but it wasn't machined out.
TDCi cases are stamped as 81D

If you have a look on my website you will see 2 pics of a LT230 transfer case, one has the allowance in the casting (not machined) the other has a blank fitted.
Land Rover Pics of our work (https://www.aztech4x4.com.au/landrover/)

[shack]

Thanks Daz,

I shall have to go investigating as I thought a box I had here didn't have the port for a switch, I'm likely wrong so I'll go check but it won't be for a few days.

[shack]

A few days later.....

The case I have is a 22D, which I make out as being for a TDI defender.

What is the purpose of the detent switch, and what is it wired too?

As far as the high low range switch goes on late model TD5 Auto D2s, there is no need for it as gear ratio monitoring kicks the engine tune over to low range mapping automatically.

I haven't looked at the V8 or manual D2, but in the defender tune it still needs the range switch for low range mapping.

[shack]

It just occurred to me this morning because of your reference to the U.S. D2.

By high low detent switch, do you mean an interlock?

[ashtrans]

Does anybody know what revision of LT230 wouldn't have a High/low switch, and more specifically what it would be fitted to?

TD5 and later have this switch, pre TD5 don't,

I understand it dampens the throttle signal when in low to make it less responsive / jerky

[Tins]

TD5 and later have this switch, pre TD5 don't,

I understand it dampens the throttle signal when in low to make it less responsive / jerky

Well, you'd know. Perhaps I'd better connect mine....

[shack]

I've known about the Hi range Low range mapping for many years, I just wasn't sure what other revisions of LT230 would have the switch - if any.

On the Auto D2, there's some extra programming and info passed between the TCU and engine ECU that negates the need for the switch. I'm not 100% sure if ALL versions of the auto setup do the same, I possibly knew at some stage but that was over 5 sleeps ago so...

The things that rely on knowing what range is selected are:

Engine surge damping.

Low range Hi range throttle mapping.

There a few other maps also but they are not used on factory tunes so I'll leave them out.

Other systems requiring Hi range Low range info are:

HDC.

Low range engine overrun/ braking incorporating TCC locking.

All shift and lock points including Adaptive shift maps, Adaptive Lock maps.

Fortunately the TCU handles this via gear ratio monitoring.

As far as I know all late D2s no longer had the low range switch wire in the loom to the engine ECU.