Auto gearbox replacement

Gorj05 · Nov 13, 2014

Hi guys, my first post, I have a p38, w reg 2000, 2.5 bmw engine, my auto gearbox made a dull thud/ clonk whilst towing my caravan, lost all gears except 1st and reverse, no warning lights on dashboard, can I replace this box with one from a 4.6 if I used my bell end.
Anyone want to buy a p38 less the cost of a box & fitting. Just thought I'd ask...
Thanks to all and would appreciate any help, frustrated newby to RR's #$$#@#

Turboman · Nov 13, 2014

Gorj05 said:
Hi guys, my first post, I have a p38, w reg 2000, 2.5 bmw engine, my auto gearbox made a dull thud/ clonk whilst towing my caravan, lost all gears except 1st and reverse, no warning lights on dashboard, can I replace this box with one from a 4.6 if I used my bell end.
Anyone want to buy a p38 less the cost of a box & fitting. Just thought I'd ask...
Thanks to all and would appreciate any help, frustrated newby to RR's #$$#@#

You have posted in the 2.5td section, they aren't fitted in rangies

Try posting it in the Range Rover forum, mate

blue beasty · Nov 13, 2014

moved

tomcat59alan · Nov 14, 2014

Gorj05 said:
Hi guys, my first post, I have a p38, w reg 2000, 2.5 bmw engine, my auto gearbox made a dull thud/ clonk whilst towing my caravan, lost all gears except 1st and reverse, no warning lights on dashboard, can I replace this box with one from a 4.6 if I used my bell end.
Anyone want to buy a p38 less the cost of a box & fitting. Just thought I'd ask...
Thanks to all and would appreciate any help, frustrated newby to RR's #$$#@#

:welcome2:I can tell you are new to this forum. You cannot change your gearbox with your bell end! you will have to use a trolley jack at least.

. I've never changed an auto box think it's a lot harder than a manual, don't know if the 4.6 bell housing will fit the 2.5 box but you will get your answer soon.

Saint.V8 · Nov 14, 2014

The diesel and the 4.0 use the same ZF4HP22 box, and the Bell Housing is different I think.....the 4.6 used a ZF4HP24 box which I think is a tad longer so you may have to change the rear propshaft or output flange do-dad thingys...

It can be done, but parts need changing, Datatek, Wammers or JamesMartin will know for sure!

Littelwill · Nov 14, 2014

Pretty sure you can use a 4.6 box but you do need to swap the Bell housing to stop it being to long....

brianp38dse · Nov 14, 2014

Datatek ,recons on fitting the hp24 box if you hsve a chipped diesel i belive its not tohard but might be wrong ,sure he will be along some time .

wammers · Nov 14, 2014

brianp38dse said:
Datatek ,recons on fitting the hp24 box if you hsve a chipped diesel i belive its not tohard but might be wrong ,sure he will be along some time .

As long as the 22 has been looked after and is sound no problems with a chip for normal driving, towing chipped is another matter.

Datatek · Nov 14, 2014

HP24 can be fitted, just the bell housing to swap and on some versions the oil pump. You use the diesel torque convertor, no change for the props.

cheongthong · Nov 14, 2014

YES , you can use the 4hp24 gearbox but have to use the the 4 hp 22 bellhouse, oil pump , the input shaft and check if the forward clutch is in good condition ,, that all

Datatek · Nov 15, 2014

I see you are from Harleston, I used to live there in the development opposite the old Howard Rotovator plant which is long gone. I think Lings Honda is on the corner of the estate now. I bought one of the bungalows new, long time ago now.

stuu · Nov 15, 2014

wammers said:
As long as the 22 has been looked after and is sound no problems with a chip for normal driving, towing chipped is another matter.

Whats wrong with towing chipped? Mine towed a horsebox with two horses every other weekend for over years before i baught it with a nackerd flex plate

wammers · Nov 15, 2014

stustrong said:
Whats wrong with towing chipped? Mine towed a horsebox with two horses every other weekend for over years before i baught it with a nackerd flex plate

Over 50 MPH the torque converter is locked up and the engine coupled direct to the gearbox with no converter slip. With a lot of weight to pull and the extra torque available it can cause the sprag clutches to let go. As i said it depends on the condition of the box and if it has been looked after. Sticking a chip on an high miler which has had less than good care is asking for trouble. Wonder what knackered the flex plate?

stuu · Nov 15, 2014

Ah okay im with you on that the box its self worked well all gears fine. Shes on 145k had regular fresh oil and a new filter every 20k one i do know is sport mode worked but manual didnt is this a possible future problem?

jamesmartin · Nov 15, 2014

wammers said:
Over 50 MPH the torque converter is locked up and the engine coupled direct to the gearbox with no converter slip. With a lot of weight to pull and the extra torque available it can cause the sprag clutches to let go. As i said it depends on the condition of the box and if it has been looked after. Sticking a chip on an high miler which has had less than good care is asking for trouble. Wonder what knackered the flex plate?

true the more torque put through the box will shorten life to clutches as well

wammers · Nov 15, 2014

jamesmartin said:
true the more torque put through the box will shorten life to clutches as well

I agree, but the 4.0 litre petrol has the same box and the same torque output as the chipped diesel but with slightly more BHP. Different torque curve yes but you don't hear of many of those knackering the box. Think it's mostly down to neglect and or sticking a chip on an high miler that has had the gearbox oil changed every Preston guild.

jamesmartin · Nov 15, 2014

wammers said:
I agree, but the 4.0 litre petrol has the same box and the same torque output as the chipped diesel but with slightly more BHP. Different torque curve yes but you don't hear of many of those knackering the box. Think it's mostly down to neglect and or sticking a chip on an high miler that has had the gearbox oil changed every Preston guild.

diesels have harsher torque more so when chipped,9 times out of 10 its a faulty diesel box ,though i wouldnt want to tow too heavy with a petrol

wammers · Nov 15, 2014

jamesmartin said:
diesels have harsher torque more so when chipped,9 times out of 10 its a faulty diesel box ,though i wouldnt want to tow too heavy with a petrol

Worn clutches are usually down to a sticky valve block cause by ****ty oil in my experience. Everything wears with use but that can certainly accelerate it. Specially if you are towing an house behind it with ****ty oil and a sticky block on a regular basis. Something has to give. Sticking a chip in it will only make things go bang quicker.

jamesmartin · Nov 15, 2014

wammers said:
Worn clutches are usually down to a sticky valve block cause by ****ty oil in my experience. Everything wears with use but that can certainly accelerate it. Specially if you are towing an house behind it with ****ty oil and a sticky block on a regular basis. Something has to give. Sticking a chip in it will only make things go bang quicker.

you can see torque effect on clutches

tomcat59alan · Nov 16, 2014

wammers said:
it's mostly down to neglect and or sticking a chip on an high miler that has had the gearbox oil changed every Preston guild.

When's the next one Tony?

Auto gearbox replacement

New Member

Mab An Gov

Leaks an prone to bits dropping off

Well-Known Member

Dyed-in-the-wool 100% RR Junkie

Well-Known Member

Well-Known Member

No longer with us, RIP

Well-Known Member

Active Member

Well-Known Member

Well-Known Member

No longer with us, RIP

Well-Known Member

Well-Known Member

No longer with us, RIP

Well-Known Member

No longer with us, RIP

Well-Known Member

Well-Known Member

Similar threads