GM 5L40E transmission Re-built to 5L50E specs

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Originally Posted by Laurie

.The basic spec for the 5L40E is below the torque output of the Td6, go figure !
What ever rebuilder who can come up with a strong auto at a reasonable cost will do very well with all the Rangies and X5's that will be needing rebuilds in the future.

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Yes that's correct Laurie R.R. GM 5L40E rated at 340Nm yet the TD6 output is 390Nm instock form. Had been in touch with one tuner who fitted large intercooler & tune for 540Nm. But he later remove this as the gearbox couldn't handle the power.

Spoke with an autotrans repairer yesterday who said the service live of the oil in GMH Commodore 5L40E was 400,000 km . To him a JOKE. Yes the box is a little bit different to whats in our R.R. but still should be serviced.

As posted elsewhere there are a couple of good treads on RangeRover.net regarding the 5L40E


Gary

If RR's using this transmission were sold in the USA then there is sure to be someone doing durability or performance mods to them, probably any number of shops. The yanks would be cheaper than virtually anyone else. Perhaps buy a Cadillac trans from a wrecker and have it delivered to a trans. shop for the work.

You could try emailing these guys for a source. They may not be doing this themselves but are quite likely to know who is.

Bob Bendtsen at Bendtsen's Transmissions, Ham Lake, Minneapolis, bbendtsen@aol.com

Paul Cangialosi, support@5speeds.com. They are down in Florida and make new Muncie trans. amongst many other achievements.

Phil Reilly, Phil Reilly Coy. San Francisco, p_reilly@pacbell.net, is another good source.

Jim Himmelsbach, Zakira's Garage, Cincinatti, jim@zakiras.com, could be worth an e-mail.


These guys are absolute founts of knowledge. They are professional restorers, modifiers, preparers.

If anyone has experience in the US and may know sources, this bloke will.

Land Rover repairs and service

Regards Philip A

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We suggest changing the "permanent" transmission fluid at 60,000 miles. No matter how good the fluid is, it will not last forever, and it carries an ever-increasing load of wear particles until it is flushed out. The ZF transmission has proven to be a weak point in these heavy trucks. It is important to use the correct blue BMW coolant in these engines. If no Land Rover coolant is available coolant can be bought from any BMW dealer.

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It occurs to me that no TD6 diesels were sold in the USA and the V8 had a ZF.Regards Philip A

Philip
Thats correct, but they sold the BMW X5 Diesel with the same gearbox ! Although it looks like BMW had updated versions of the box, going by the different part numbers. And as stated above they would replace not rebuild.

From left field

Why can’t the ZF 5HP24 be modified for the diesel ? There are plenty of these autos around being installed in RR V8,bmw,Jaguar and Audi
What would need modifying ?
Bellhousing modified or replaced (ZF’s used on later Td6 X5’s)
Lowering the stall speed of the converter ?
Re-program ECU ?

This auto was beefed up in the 5HP24A version for Audi C5 RS6 Quattro where the V8 put out 331 kilowatts (450 PS; 444 bhp) at 5,700 to 6,400 rpm, and generated 560 newton metres (413 ft•lbf) of torque.

With gear ratios below I can’t see a problem with a slightly lower first, lower reverse and a slightly taller O/D


Gear Ratios 1 2 3 4 5 R


GM 5L40/50E 3.42 2.21 1.60 1.00 0.75 3.02
ZF 5HP24 3.57 2.20 1.51 1.00 0.80 4.10
ZF 5HP24A 3.57 2.20 1.51 1.00 0.80 4.10

Interested to hear any opinions or ideas.
Laurie

Any one have any ideas on any alternate gearbox ?

Laurie

I don't think it is beyond the realms of possibility, I think it is more a matter of someone biting the bullet and doing it. Unfortunately, I don't have the experience or knowledge to try something like this. I am suprised that no one has tried a conversion of some description though. I think it is just a matter of time before someone has a crack, as more and more of these vehicles are getting to the point where thier trannies will fail. Once I am back on the road, I should have a few years to think about this, but as I plan to keep mine a long time, maybe By the next time mine fails, someone will have come up with something.

What are the dimesions of the ZF, and are the transfer cases the same on the V8's?

I can't see why it couldn't be done....

G,Day Guys

The auto (5L80e) was the main deal breaker for me so I decided to go with a supercharged L322 and not the TD6.

A mate owns a well known auto workshop (specialising in 4WDs and auto mods) in the SE suburbs of Melbourne and as I was keen on a TD6 and knew about the auto being the week link I asked the same question, when the auto goes bang why can we fit the ZF 6 speed ?

His advice was it wouldn't make more economic sense and would be cheaper to just buy a supercharged L322 with the 6 speed ZF in it (he also made the comment I don't hang onto my cars long enough to even think of such a conversion LOL).

From what was put to me, with a conversion like that most of the problems are computer related. Anything is possible but how much money do you want to throw at it and time sorting it out ???.

I figured for the money it would cost for the conversion, it would more than offset the extra thirst of the S/C V8 and make more economic sense short and long term.

On another note the best fuel consumption I have got out of it around town is 15ltr per 100kms which I dint think was to bad considering it has a 297KW V8. Mind you if you use a lot of right foot (which isn't hard, I love the power) it loves a drink. I know you blokes with TD6 getting your 8ltrs per 100kms will be laughing at fuel figures like that.

Cheers

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Originally Posted by RR46

On another note the best fuel consumption I have got out of it around town is 15ltr per 100kms which I dint think was to bad considering it has a 297KW V8. Mind you if you use a lot of right foot (which isn't hard, I love the power) it loves a drink. I know you blokes with TD6 getting your 8ltrs per 100kms will be laughing at fuel figures like that.

Cheers

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There's the rub. You summed it up with that last paragraph. I went for the TD6 because of the fuel economy, and I knew the trannie may be an issue.

Based on your 'best' around town figures, and that I will do about 25,000km a year, at say an average of 10/100, you would be using 3,750 litres of fuel, to my 2,500 ltrs. At todays prices, that's about $1,750 a year. If I run mine for 10 years, that's over $17K in less in fuel! To me, even if I use a couple of extra trannies, or pay to get a ZF to fit, I still think I would be miles in front financially at the end, and I haven't even mentioned how much longer a well maintained diesel will last compared to a petrol...

I know the V8 trannie will cause less issues, but I just couldn't afford to run one... more- The old 3.5 in my Classic sure knows how to drink:p, but that's why it's only my weekend toy.

Cheers - Gav