Auto gearbox issues

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Anyway, if I were you this is what I'd do:
1. Measure the solenoids as per Hippo's vid. If that doesn't reveal a problem (it didn't in my case)...
2. According to my magic LR manual, your symptoms could be a sign of excess oil pressure, which could be caused by too much oil, the wrong oil or a faulty line pressure solenoid. Buy some known good ATF and do a full change.(instructions here). Note the old oil - does it smell burnt? If so could be a clutch band problem, which is not good. Otherwise...
3. Replace the line pressure solenoid. It's a little tricky but not that hard. You'll find it easier to remove the front plate if you drop the oil cooler first, so you'll have to drain it a bit. If you've bought 20 litres of fluid, you'll be very pleased at this point :)
4. If after all that it still isn't happy there are a few more solenoids you can try, but you can decide when you get there.

Note that to do a full fluid change you'll need to do a partial change as per the instructions, then disconnect the oil cooler and allow it to drain the torque converter, but you'll need someone to switch-off the engine quick when the clean stuff starts coming through.

I tried to attach the LR manual I referred to but it's too big so PM me your email if you want it, loads of very useful info in there about the Jatco box including probable fixes and plenty besides.

Done a level check and was over by about .75 litre, What came out was brown but not smelling burnt so I did a partial change. Took out about 3 litres and replaced with fresh and checked the level. Went for a drive but symptoms still there. But after about 15 miles I stopped for a couple of minutes and when I started again the gearbox was perfect again. When I came back to it later on this evening the problems had returned.
So now need to get said multi meter out and see where that takes me.:mad::mad::mad::mad::mad:
 
may I ask a daft question plse

could the gearbox ecu cause any of this, ie if the main part of the brains don't tell the solenoids to change correctly could this cause the problems

the reason I ask is if by turning the car off and then back on again it clears the fault could that be like resetting a computer, ????

just a thought , I don't know enough about these boxes , only how to do the oil change and just curiuos if an intermittent problem with an ecu may possibly be at fault

would something like a hawkeye show up what's faulty

thks and hope u didn't mind me asking a daft question
 
may I ask a daft question plse

could the gearbox ecu cause any of this, ie if the main part of the brains don't tell the solenoids to change correctly could this cause the problems

the reason I ask is if by turning the car off and then back on again it clears the fault could that be like resetting a computer, ????

just a thought , I don't know enough about these boxes , only how to do the oil change and just curiuos if an intermittent problem with an ecu may possibly be at fault

would something like a hawkeye show up what's faulty

thks and hope u didn't mind me asking a daft question

There are no daft questions.

On the subject of the ECU, I spoke to a chap who's Land Rover was stolen. It was recovered at the docks and the battery had been disconnected for weeks, something to do with the alarm I think. However when it was reconnected and charged he said it drove like a completely different car. Apparently the ECU has to relearn everything as it doesn't like not being connected to 12 volts. How true this is I do not Know but I didn't see any flying pigs lol. :rolleyes::rolleyes:
 
Solenoids now tested and the results are:-
Brake duty solenoid - 1.48. Should be 2.6 to 3.2 ohms (then 0 reading)
Brake timing solenoid 19.3. Should be 14 to 18ohms
Reduction timing solenoid valve 19.3. Should be 14 to 18 ohms
Shift solenoid valve B 19.5. Should be 14 to 18 ohms
Shift solenoid valve A 19.1. Should be 14 to 18 ohms.
Lock up solenoid valve 15.4. Should be 12 to 13.2 ohms.
Line pressure duty solenoid valve 4. Should be 2.6 to 3.2 ohms.
Shift solenoid valve C 19.3. Should be 14 to 18 ohms.
Low clutch timing solenoid valve 19.1. Should be 14 to 18 ohms.

Make of that what you will please gentlemen, and let me have your views. I feel it is inevitable that at least the "brake duty solenoid valve is u/s.

As for the rest they all seem out by about the same margin so possibly an issue with the meter and not the solenoids. I am rather spoilt in that I have access to the company workshop so trying a different meter to get a cross reference shouldn't be problem.

Will let you know.
 
The high readings could be due to temperature.
But the brake duty solenoid looks very wrong. It controls the pressure so it could be your culprit.

From the manual:
No pressure control will occur therefore gear changes from fifth gear will be very harsh (2-4 brake duty solenoid
valve failure).
 
The high readings could be due to temperature.
But the brake duty solenoid looks very wrong. It controls the pressure so it could be your culprit.

From the manual:
Quote:4

No pressure control will occur therefore gear changes from fifth gear will be very harsh (2-4 brake duty solenoid
valve failure).

All sounds very reasonable and I do agree about the "brake solenoid valve" but the changes form 4th to 5th and back again are pretty smooth. It is the change from 1st through to 3rd and back again that are the issue. That said if I go in for one or more solenoids then I may as well go in for the lot.
One or two more little things to check and then decisions must be made.


:eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek:
 
When (not if!) it happens to my wife's Hippo, I'll replace all solenoids as a kit. Once the oil cooler is out of the way, and the plate is off, replacing solenoids is a child's play.

Doing it on the ground might be a bitch, but on the hoist it's easy-peasy.
 
OK assuming that I m going to change all the solenoids, who can point me in the right direction for quality replacements at a good price. To those that have done this before, what exactly will I need by way of parts and fluids and time, I am good at twirling the spanners and will do the initial dismantling with the SOB on four axle stands. The only thing that might slow me down is my mobility (two hip replacements ) but I am a stubborn old git and would rather do this myself. Even if it only saves me a tenner. Knowledge is a powerful tool.

:D:p
 
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Solenoids now tested and the results are:-
Brake duty solenoid - 1.48. Should be 2.6 to 3.2 ohms (then 0 reading)
Brake timing solenoid 19.3. Should be 14 to 18ohms
Reduction timing solenoid valve 19.3. Should be 14 to 18 ohms
Shift solenoid valve B 19.5. Should be 14 to 18 ohms
Shift solenoid valve A 19.1. Should be 14 to 18 ohms.
Lock up solenoid valve 15.4. Should be 12 to 13.2 ohms.
Line pressure duty solenoid valve 4. Should be 2.6 to 3.2 ohms.
Shift solenoid valve C 19.3. Should be 14 to 18 ohms.
Low clutch timing solenoid valve 19.1. Should be 14 to 18 ohms.

Make of that what you will please gentlemen, and let me have your views. I feel it is inevitable that at least the "brake duty solenoid valve is u/s.

As for the rest they all seem out by about the same margin so possibly an issue with the meter and not the solenoids. I am rather spoilt in that I have access to the company workshop so trying a different meter to get a cross reference shouldn't be problem.

Will let you know.


Update on readings.

Now measured at the correct temperatures ( thanks to bukko, font of all knowledge) All readings correct except - vehicle speed sensor, no reading. Brake duty solenoid valve - no reading.

Everything else absolutely spot on. Unless anybody knows different, I can feel a trip to the gearbox specialists coming on at a cost of £600. That said spoke to another Range Rover auto owner who said he wouldn't touch them with a poopy stick :mad::mad::mad::mad::mad::mad::mad::mad::mad::mad::mad::mad:
 
thanks to bukko, font of all knowledge

Thanks :) But that's not me - everything I know I read on this site!

Have you got an independent Land Rover / Rover garage near you?
I'm sure if you buy the solenoid they'll replace it if you don't feel comfortable doing it yourself.

Not sure about the speed sensor though, that's a bigger job.
But, I'd still be tempted to replace the solenoid just for the hell of it, as it could be an easy fix.
 
jpat.co.uk has been well recommended by others in the UK.


Well here's the good bit jpat.co.uk will do the solenoid for £33 and the speed sensor for £10 + postage. Or the whole solenoid kit for £176 and throw in the service manual. Course of action I think is to do all the solenoids and then see where we are at. Apparently the speed sensor is easy but it's a gearbox out job, still something I can do but not sure that I want to.
 
Well here's the good bit jpat.co.uk will do the solenoid for £33 and the speed sensor for £10 + postage. Or the whole solenoid kit for £176 and throw in the service manual. Course of action I think is to do all the solenoids and then see where we are at. Apparently the speed sensor is easy but it's a gearbox out job, still something I can do but not sure that I want to.


It's been a while coming, but due to work commitments and marriage break up I have not until now had time to do this.

On the plus side, thanks to all on here that have offered advice. It has all been relevant and extremely accurate.

I ended up getting all 9 solenoids for £50 from a contact in the trade and was then given full use of a fully equipped workshop that was closed over xmas . Could not have been timed better.

The dismantling whilst not as completely straightforward as some would claim was still not a problem. The removal of the old solenoids does present a couple of problems to the first timer like myself. But nothing that a bit of common sense can't workout.

I am really pleased that I have done this as it has returned my Landy to the 'luxury' drive that it once was. All done and completed in @ 4 hours at a cost of £90.

Having done it once, I would happily do it again and am more than happy to offer advice / guidance for anyone else wishing to carry out this maintenance.

Once again thanks to all for their advice and technical know how, without this advice I would probably have scrapped my car.

:clap2::clap2::clap2::clap2::clap2::clap2::clap2:
 
Did you get hold of a service manual telling you how to change the solenoids or do they come with advice/instructions?

Nice to get feedback on it being fixed.
 
Did you get hold of a service manual telling you how to change the solenoids or do they come with advice/instructions?

Nice to get feedback on it being fixed.

No manual etc, everything I learnt was from this site and then a bit of common sense. If you can twirl a spanner and work stuff out it is easy, took me four hours. If I had to do it again I think that you could comfortably knock an hour off.

So once again, an immense thank you to all the help and advice from you guys,

If anybody needs advice etc then contact me by PM
 
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