P38 V8 auto->manual swap

Hello all,

I'm new to the forum.

I don't have a P38 yet, but would like to pick one up and convert it to an R380 manual. Here in the US, we only got V8 auto P38 Range Rovers. I know that there are many different R380s and it would be easiest to us one that came out of a V8 P38.

What I'm wondering is if anybody has done this swap before on a V8 and what information they might have. For instance, as far as I can tell, the GEMS ECUs should work on both auto and manual, 4.0 and 4.6 without replacement, but the newer Bosch ones don't.

So if anybody has information about what parts are required for the swap, any issues that they had, etc I'd greatly appreciate it.

Thanks,
Brett

Forget it,the auto works so well and the R380 manual box is horrible - getting spares for it will be difficult too,manual P38's here in the UK are mostly nasty low spec diesels - which are now well worn.

eightinavee,

Thanks for the reply, but we'll have to agree to disagree in regards to the transmission. I'm not interested in any way in owning an automatic. I won't even consider a RR if this swap can't be done and I would have the swap parts on-hand before purchasing the truck.

I'm surprised that people are ok with the auto. I've driven a couple of RRs and an LR3 and found the transmission to be frustrating at best. I've also driven a few Disco1s w/ the R380 and a Defender (all w/ the 3.9/4.0 V8) w/ the R380 and I thought the transmission was great and more than capable.

Parts being difficult to find I can deal with. There are plenty of places that have R380 rebuild kits, so after my initial gathering of parts I shouldn't have to worry about much other than the clutch and flywheel. The master/slave cylinders and the bearings seem to be readily available on eBay.

Thanks again,
Brett

eightinavee said:

Forget it,the auto works so well and the R380 manual box is horrible - getting spares for it will be difficult too,manual P38's here in the UK are mostly nasty low spec diesels - which are now well worn.

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You just don't like stirring the cogs do you 8.i.v, give me manual over a auto anyday..

and those "manual P38's here in the UK are mostly nasty low spec diesels - which are now well worn." not necessarily there are a few low mileage vehicles about...even a few high spec HSE diesels.

OK,I'm totally wrong.they are all brilliant,lovely gearboxes fitted to cars with low miles,high spec etc,etc.
Shame I've never seen any of them,all the ones I repair are near death,with virtually no synchro action on second and third gear and a heavy clutch.
Lets face it the R380 box has never been any good,the best thing they have done is to give the Ashcroft family something to do.The term "shift quality" cant really be used in the same sentence as R380 unless you include something like rubbish.
I dont mind manual boxes,but synchromesh is a basic requirement.....

The one I had snapped the output shaft where a rollpin went through. This just pulling out of a junction. Around a £500 rebuild and two years later it was shagged again. You could move the input shaft up and down about 2". Not nice boxes and VERY heavy clutches as 8inaV says. I'm glad someone agrees with me on this one. I know there'll be many that won't though.

look at that, a bloke after my own heart. i bought a diesel p38 auto and converted it to manual soon after buying it, the conversion aint a bad job really. parts for the diesel where
gearbox
gearbox wiring loom
transfer box contoller
pedal box
clutch
dual mass flywheel
master, slave cylinder and pipe work
section of loom to go upto where the low range button goes and switch
reprogram becm
engine ecu (mines a diesel so!)
gear stick and replacement wood trim
clutch pedal switch
sorted, now buy all the bits and get stuck in.

eightinavee said:

OK,I'm totally wrong.they are all brilliant,lovely gearboxes fitted to cars with low miles,high spec etc,etc.
Shame I've never seen any of them,all the ones I repair are near death,with virtually no synchro action on second and third gear and a heavy clutch.
Lets face it the R380 box has never been any good,the best thing they have done is to give the Ashcroft family something to do.The term "shift quality" cant really be used in the same sentence as R380 unless you include something like rubbish.
I dont mind manual boxes,but synchromesh is a basic requirement.....

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Land Rover have never had a good track record in choosing/designing a decent gearbox. Maybe they should strip a FJ40 gearbox/transfer case, a mate run a 4 speed behind a 400 cu in chev in an AWDC comp motor, the gearbox stood 400+ bhp. Agricultural yes but they can stand the abuse/power

The fact that the clutch is heavy and the "shift quality" is not like a car is outside the scope of the question. In fact I readily accept and even expect that because it's a truck. In that regard both of those qualities are much better than the 6-spd ZF in my Chevy 2500HD truck. But it's a giant truck and I welcome the clutch feel.

So...with that out of the way...

aaron beast unleashed,

Thanks for the list, I suspect mine will be similar for the V8. I think I won't have to change my engine computer, and therefore I don't think I'll have to reprogram my BECM. Did you reprogram that because of the ECU swap?

Was there also a different transmission brace you had to get?

My biggest expense is going to be shipping the transmission and flywheel from the UK (or somewhere else that had the P38/V8/manual). The only additional information that could be useful is if converting a Disco1 R380 to a P38 R380 is doable. If it's as simple as changing the bellhousing or input shaft or something like that, then that would save me a significant amount of shipping cost.

Thanks again,
Brett

Hullie said:

Was there also a different transmission brace you had to get?

My biggest expense is going to be shipping the transmission and flywheel from the UK (or somewhere else that had the P38/V8/manual). The only additional information that could be useful is if converting a Disco1 R380 to a P38 R380 is doable. If it's as simple as changing the bellhousing or input shaft or something like that, then that would save me a significant amount of shipping cost.

Thanks again,
Brett

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Hullie, open the link below and download the workshop manuals for the P39 and Disco, plus "MicroCat Parts" a complete parts list for Land/Range Rover.

http://green-oval.com/joomla/index.php?option=com_docman&task=cat_view&gid=13&Itemid=29

I have seen somewhere a 2009 version of MicroCat is available but have mislaid the link....

hth

zzr

Hullie said:

The fact that the clutch is heavy and the "shift quality" is not like a car is outside the scope of the question. In fact I readily accept and even expect that because it's a truck. In that regard both of those qualities are much better than the 6-spd ZF in my Chevy 2500HD truck. But it's a giant truck and I welcome the clutch feel.

So...with that out of the way...

aaron beast unleashed,

Thanks for the list, I suspect mine will be similar for the V8. I think I won't have to change my engine computer, and therefore I don't think I'll have to reprogram my BECM. Did you reprogram that because of the ECU swap?

Was there also a different transmission brace you had to get?

My biggest expense is going to be shipping the transmission and flywheel from the UK (or somewhere else that had the P38/V8/manual). The only additional information that could be useful is if converting a Disco1 R380 to a P38 R380 is doable. If it's as simple as changing the bellhousing or input shaft or something like that, then that would save me a significant amount of shipping cost.

Thanks again,
Brett

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the transmission brace is the same from auto to manual as is the transfer box, the becm will still need telling its now a manual otherwise it wont start because its waiting for a signal to say its in park or neutral if you know what i mean. if you got a rovacom go into becm and then into settings, you will see a section thats got auto or manual and the auto is highlighted until you swap it.i think theres to much work to make a disco r380 fit, the only thing that is the same is the box its self. the bellhousing, remote and output shaft i think are different. if you need any info pm me and i will do my best to help.

hi 'hullie' (please excuse my threads as i'm new to this lark) i'm with you on this, i wish to convert my 4.0 v8 auto (gems) to manual r380. i seem to be able to get my hands on all the parts required. have you procceded with your conversion yet? I hope to find someone who has seen this through to drivability before commmencing. My reasons are because I tow a caravan, and sometimes a car trailer, and run a v8 on sequential lpg, it gives me the power, and piece of mind, to keep up with traffic going up inclines, and lanes, without stamping the pedals, and changing up and down when you dont want to. (nothing worse than a lorry trying to carry momentum up a hill coming up your rear) I also have improved the running of my p38 here and there, and have now sourced a near new v8 4.6 engine, that has been modded for a little more torque with a cam, and triple angle valve seats, and mild porting. which i intend to fit at the same time. It's lpg, and my MOT tester doesnt require the lamda test, i will de-catalist at the same time I already have a sports exhaust, and its straight through. So, the car with be slightly transformed, and i can hold out a 3rd gear going up an incline, WITHOUT flooring it. i chose my 4.0 carefully for the drivability, against a diesel with manual box, after driving a few. I realise i will get a little less MPG on the 4.6, but gain with the manual box. Pound for pound (£) i think i will still be a little better off on lpg (already fitted) against dreadful diesel power. (even in manual form) -anyone else have any comments?

I accept the auto box drives well, but with a 'van on the back, it very different. and yes, some boxes wear, and they are an old Leyland Jaguar design from many years ago.

-also, (when finished) the car will sound quite nice too.

(and lads, we have to have something to keep us busy at weekends, dont we?> otherwise we get dragged around furniture shops, and supermarkets. )

Nothing better than auto for towing in my opinion, no need to burn the clutch reversing up a slope into place or select low range and you can always use the gear lever to select and hold a gear

i did the conversion from start to finish, its not a big problem just time consuming. and less of the slugish diesel talk, mines a diesel and it goes like hell know its had some tweeks and can quite easiley out drag a 4.6 v8.

arron beast unleashed said:

i did the conversion from start to finish, its not a big problem just time consuming. and less of the slugish diesel talk, mines a diesel and it goes like hell know its had some tweeks and can quite easiley out drag a 4.6 v8.

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Well, that's a mighty bit bragg, coming from a diesel. you must have chipped and intercooled the thing. -tell us please.
from my experience, i needed a tow car. So without a caravan i set out with family onboard and we tested a couple of p38 diesels. and auto, -blimey, felt like the invisible caravan was on the back with the handbrake on! the manual was better, but i must admit to stalling it a few times, as i believe you need to welly them up to drive off, especially with family etc. i did see a chipped one for sale manual but it was too far away.
we tried a couple of v8's and though the fuel prospects were poor we had to opt for it. and went 4.0 auto. i retro fitted a secondhand LPG system, and chipped it with Mark Adams optimax (RPI) and it gives great savings. i reckon better than a diesel. i couldnt find any high(ish) mpg figures to big up the diesels. as for previous entry regarding 'nothing easier than holding gears on an auto' etc, yes, we do that already. but it still slushes up hills/inclines. Not like a manual. -previous car/caravan was a manual 525i bmw touring, -perfect and 28mpg on tow. larger 6 berth now, so going for the manual conversion. I've done this job a couple of times in the past but on much older (easier) cars. and if auto's are so good, then why are all commercial vehicles manual? yes, buses have a auto variation, but they sit in traffic, and only pull out as you approach them.

So, it looks like a heavy hardware changeover, fit the manual pedals, fit hydraulics, that all seems straighforward, pop the y pice manifold back on...but then there is the loom up to the hi/lo switch? does that plug in the the plate holding the gearstick? then there's the existing gearbox ecu loom? what do i do there please? and reverse switch, i also seem to remember seeing that the manual diesel has gearbox cooler pipes, and v8 has none? cant be right surely? the only problems i think worry me are the wiring. -getting parts from the doner and getting it in before remaining car is crushed etc. and yes, i suppose getting someone over to tell the becm etc. unless i figure out the autobox wiring colours and bridge them leaving it in permanent neutral, only broken by reverse.......

one last thing, will cruise control still work, for those days without the caravan?

johnboyairey said:

Well, that's a mighty bit bragg, coming from a diesel. you must have chipped and intercooled the thing. -tell us please.
from my experience, i needed a tow car. So without a caravan i set out with family onboard and we tested a couple of p38 diesels. and auto, -blimey, felt like the invisible caravan was on the back with the handbrake on! the manual was better, but i must admit to stalling it a few times, as i believe you need to welly them up to drive off, especially with family etc. i did see a chipped one for sale manual but it was too far away.
we tried a couple of v8's and though the fuel prospects were poor we had to opt for it. and went 4.0 auto. i retro fitted a secondhand LPG system, and chipped it with Mark Adams optimax (RPI) and it gives great savings. i reckon better than a diesel. i couldnt find any high(ish) mpg figures to big up the diesels. as for previous entry regarding 'nothing easier than holding gears on an auto' etc, yes, we do that already. but it still slushes up hills/inclines. Not like a manual. -previous car/caravan was a manual 525i bmw touring, -perfect and 28mpg on tow. larger 6 berth now, so going for the manual conversion. I've done this job a couple of times in the past but on much older (easier) cars. and if auto's are so good, then why are all commercial vehicles manual? yes, buses have a auto variation, but they sit in traffic, and only pull out as you approach them.

So, it looks like a heavy hardware changeover, fit the manual pedals, fit hydraulics, that all seems straighforward, pop the y pice manifold back on...but then there is the loom up to the hi/lo switch? does that plug in the the plate holding the gearstick? then there's the existing gearbox ecu loom? what do i do there please? and reverse switch, i also seem to remember seeing that the manual diesel has gearbox cooler pipes, and v8 has none? cant be right surely? the only problems i think worry me are the wiring. -getting parts from the doner and getting it in before remaining car is crushed etc. and yes, i suppose getting someone over to tell the becm etc. unless i figure out the autobox wiring colours and bridge them leaving it in permanent neutral, only broken by reverse.......

one last thing, will cruise control still work, for those days without the caravan?

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You don't use cruise with the caravan Works fine on my diesel even with 2 tonnes plus on the trailer, I use it all the time when I've got a decent run to do

hi there,i got a 95 p38 with manual box,i heard that the manauls are special orders,ne way mine is a dream,smooth as silk when changing,nice bit of kit.