As above.

If it was me id be hunting out a 2005/4 box and getting that rebuilt as they changed code and some parts.

Or ideally get a 5l50 box and swap the core into the 5l40 once rebuilt. It can handle more torque, has more clutch packs and an even more modified version can be mated up to an ls1 engine which produces twice the torque of a standard td6 and hasn't blown the box apart yet from what I can see online.

Suggested this to Migs as the best way forward for his work as long term any box will struggle but an uprated one for a lot more power would be better as it will be the clutch packs that suffer the most wear, especially in vehicles carrying more weight around on average. FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

The only problem with the 5L50E parts integration is.... finding a bloody box to integrate

I have been thinking about this a lot... and I still have my doubts.... the LS7 wont get any where near full torque until it's in the high rev range, where as the range rover Td6 gets to full steam ahead at very low revs, just when it's struggling to get the whole show rolling... I still think that momentum has a lot to play in this.....

Anyhow I found a much better solution....a ML270CDI Manual  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Later X5's have them fitted and some other BMW's,

But this is the ls1 power graph... Flatter torque curve than a td6 and this is before it even gets breathed on at all. The one that went in with the modded box had work done on it as well...
 FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

Well by 2004 BMW had ditched the GM box for a ZF, and not to point out that they never fitted the GM gearbox to the 7 series at all...... although the 7 series got the M57 diesel engine, it was mated to a ZF automatic gearbox and only tipped the scales at 1.9 tons......

As I have stated before it's not like they never fitted a Land Rover transfer box to a ZF gearbox, and equally they never mated the M57 engine to anything other than the GM box, I suspect that BMW had a heap of GM boxes to get rid of, they knew that they would work to a fashion and go beyond the warranty, without any problems, saw the opportunity to get shot and forced them on Land Rover... A case of this or nothing..... Gits

I think that under normal use the GM5L40E will work fine and return a reasonably good mileage, but having used one for extreme towing I would not even recommend it to someone that I didn't like...

If you keep the trailer weight under 2 tons then, I think, it will last forever, well as long as it's possible to get out of a GM box  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Right Mr King Pleb.... this 'ere LS1 GM5L40E / 5L50E gearbox hybrid that you keep harping on about, I have looked a little further in to what it is in... A Pontiac Solstice...... it's a "sports car" in the American sense of the term, I always though that a sports car was a manual... It only weighs 1.3 tons curb weight.... that's everything except the driver.... so unless your suggesting that 2 American adults can make up the missing 1.32 tons... it is of no comparison to a Range Rover....

That's like saying that a Smart Car and a Unimog are the same because they are made by the same company Only Joking... everyone knows that the Smart Car is made by Addis... it's their up market wheelie bin range  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

addias!!!! 1937 model y hot rod 1000bhp rover75 v8 vincert blackshadow plus several boats and other toyz ! ford f150 raptor Mercedes e class convertible jaguar f pace

Addias ???? they make shoes.... if you put Addis products on your feet you'd be wearing these

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