One for the Gearbox Gurus

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.

ovalandrover

Well-Known Member
Posts
1,603
ever since I have had this car (3 years and 60 000 miles )I have had an intermittent fault and that is when the car is going downhill with no throttle it kicks out of gear and stalls beeps and shows gearbox fault on dash. just recently it has got more frequent and also after about 2 hrs running while cruising and braking it beeps and then I lose the lock up in 4 gear. stop and restart it ok for a while.
Yesterday when going down hillon a rough road in Mongolia it stalled as it had done before but when I restarted this time the gear change pattern had changed and it would not change from first to second below 3500 rpm and from second to third below 3750 rpm .
I thought I had lost 4 th gear as I was on a jeep track and could not go over 40 mph and mostly below 25 mph.
up changes
1st to 2nd 35mph
2nd to 3rd 48mph
3rd to 4th 70mph
When I got onto a highway i had to get up to 70 mph which is about 3700 rpm before it would go into 4th and T/C lock up.
The down change are high as well .
4th to 3rd 60mph
3rd to 2nd 48mph
2nd to 1st 30mph
I checked oil level best i could on the track and it seemed OK if a bit overfull which it was not when it was checked 10000 miles ago.
Tomorrow I will drop the sump and clean out the valve block and check for debris in the sump and then decide what to do.
I have a Nanacom and it does not register any faults on the gearbox either stationary or going But what it does do is most of the time when i try to read setting or inputs is lock up or go back to Nanacom start up screen and not give any readings at all. so if I cant find any sticky valves or other faults I will try to find the LR dealer and get it on test book.
I have read Rave and there is a speed sensor in the valve block but it seems it is for sending information to diagnostic and does not do anything else.
Any one who has any knowledge of these boxes and has come across similar faults I would much appreciate any input as to what is wrong.
Thank You
 
Almost like it's in sport mode. There are a couple of speed sensors if I rememeber correctly which give input shaft speed and output speed or maybe I'm dreaming.
 
It is even higher changes than in sports mode.
I didn't mention that i have also waded it through about 700 mm deep river for about 100 m so maybe some water has got into the system but that was 1 days before the fault showed and no water entered the cab.
Low Ratio changes seem normal except for 4 th which was high and manual mode was ok.
 
It is even higher changes than in sports mode.
I didn't mention that i have also waded it through about 700 mm deep river for about 100 m so maybe some water has got into the system but that was 1 days before the fault showed and no water entered the cab.
Low Ratio changes seem normal except for 4 th which was high and manual mode was ok.
Lots of connectors under the car to corrode as the water dries out. Transfer box ECU problems have been known to affect shift patterns.
 
Lots of connectors under the car to corrode as the water dries out. Transfer box ECU problems have been known to affect shift patterns.
They will also be checked tomorrow when I get the car over a pit.
Spares are also a problem out here but if I had a new one there would not be a problem as they have only just started importing Range Rovers and only keeps spares for the L322
 
Last edited:
:confused:
I thought we were talking P38:confused:

We are talking P38 and there are no spares for them here in Mongolia as the new rich goat herders and miners only want new cars. But there is a place called the black market where you can get almost anything for jap or korean cars and russian ones as well but you dont see many russian cars here but the chinese motor bikes are everywhere
 
first thing i would do is check oil ,no lr unit is truly water proof

Oil was checked as soon as I got to a place with hard standing it was not milky. but tomorrow it will be drained and the valve block cleaned and the sump checked for debris.
I still think it has something to do with the stalling that has been happening since I owned the car.
I have done a search on the stalling issue and found one other thread with similar issues but no one seems to know what causes it.
 
Update on the gearbox problems!
took out valve block stripped down and refitted now I only have 1st and reverse gear.
Obviously I have assembled the valves wrong somewhere.
Does anyone have an exploded view of the valve block with all the valves. springs, balls and restrictor valves.
The oil was OK and there was no smell of burning and I refilled with 8 lts of new oil so it should not be low.
Other than that does anyone have a valve block that they can sell me and ship it to Mongolia via UPS I am willing to pay by bank transfer or any other method.
I can get a secondhand gearbox ECU but dont know about a valve block.
I will try later when you are awake over there.
 
Update on the gearbox problems!
took out valve block stripped down and refitted now I only have 1st and reverse gear.
Obviously I have assembled the valves wrong somewhere.
Does anyone have an exploded view of the valve block with all the valves. springs, balls and restrictor valves.
The oil was OK and there was no smell of burning and I refilled with 8 lts of new oil so it should not be low.
Other than that does anyone have a valve block that they can sell me and ship it to Mongolia via UPS I am willing to pay by bank transfer or any other method.
I can get a secondhand gearbox ECU but dont know about a valve block.
I will try later when you are awake over there.
PM me with an email address and I will send you a complete PDF diagnostic guide. I tried to insert it but it's too big a file.:)
 
Thank you Data for the file I think its going to be a great help and as for not taking your Range Rover to places I go you are missing out on lot of great experiences.
I cant say I have had any serious problems with this car that cant be fixed and I have done 60 000 mile since i bought it and most of that has been in out of the way places and this is the second time in Mongolia with it.
If I have to fly back and get a recon gearbox I will.It may be expensive but its my Hotel and transport all in one.
:crazy_driver:
this is about the way to describe drivers here they will take on trucks with their toyota yaris and win because they have no fear No wonder Gengis Kahn conquered half the know world in the 13 centuary
 
Update.
I have sorted the valve block out with the diagrams supplied by Datatek but still have the original problem so I am tryining to source a gearbox ECU part no UHC 100 140 if anyone knows of one and can send it to Mongolia via UPS or DHL I would appreciate it or I will have to put up with this fault untill I get back to the UK.
I will try and find someone with test book here but at the moment we are in the Middle of The Nadam festival and everyone is either at the wrestling or Horse events or getting high on fermented mares milk so for the next few days nothing happens in Ulaan Baatar
 
Update on the gearbox problems!
took out valve block stripped down and refitted now I only have 1st and reverse gear.
Obviously I have assembled the valves wrong somewhere.
Does anyone have an exploded view of the valve block with all the valves. springs, balls and restrictor valves.
The oil was OK and there was no smell of burning and I refilled with 8 lts of new oil so it should not be low.
Other than that does anyone have a valve block that they can sell me and ship it to Mongolia via UPS I am willing to pay by bank transfer or any other method.
I can get a secondhand gearbox ECU but dont know about a valve block.
I will try later when you are awake over there.

The auto ECU is pretty reliable, odd happenings with shifts are often down to the transfer box ECU, open it up and look for signs of burning before you spend on an auto box ECU..
 
I have had the valve block out for a second time and found that the 2 retainer clips were in the wrong holes in the valve block and one was the wrong way round but I also found that one of the valve was in the wrong way round so changed it round.
when I road tested it I was back to high changes but had all the gears again BUT selecting reverse was very soft and had to rev the engine to engage it so im wondering if the manual has the picture of the valve I changed wrong because I was very carefully to note the way they came out and replaced them accordingly.
I will do some further research and see what I can find out and let you know.
I will also try to fool the computer into thinking it is in low ratio when in high range and get the manual mode working in high range instead of the sport mode
 
Had overlander over today tried both nano's his and mine no faults out put and speed sensors match but overlanders nano cuts out sometimes .
removed power box had inlet manifold off the ecu sensor green part had come away from its brass fitting new one fitted .
Timing mod is out reading 23 I've lent him the tools to rectifie this
Gearbox is still playing up.

We are sure the TQ is slipping power box didn't really make any changes

So its off to ashcrofts for a check over

I have a question do all the ecu for the diesels work in each other apart from the becm as the gearbox ecu seem to have 4 different types ????

And like mine no air con water sensor or any loom/ plug for it .

I do believe if one was fitted it was only on the 2001 year.
 
Last edited:
Moral of this is don't play with things you know nothing about. Unless you do it every day, NEVER strip a valve block down without a service sheet and a partitioned box for storing related components. Springs that have lost their colour codes may look the same but have different rates and CANNOT be transposed.
 
Moral of this is don't play with things you know nothing about. Unless you do it every day, NEVER strip a valve block down without a service sheet and a partitioned box for storing related components. Springs that have lost their colour codes may look the same but have different rates and CANNOT be transposed.

Wammers when your stuck in a foreign county you might have no choice since then a new box and TQ is fitted.
 
Back
Top