W

weimieman

Active Member
Here's a strange one guru's .....

What I thought might be a simple service problem (it wasn't), I've sort of stumbled across a temporary solution.

When in auto mode, when in top gear around 30 -40 mph, the engine would stumble at the same point in every cycle which I hoped would be plugs or timing but after a full service the problem remained. However, whilst playing around trying to tweak the most out of the mpg (yeah I know, dead horse and all that), I started playing around in manual mode and guess what, between 30 and 40 it's perfect. No stutter, no drop in revs - nothing. That kinda gets me paranoid that its an internal gearbox problem as I've heard so many horror stories about watching out for the box around 100K. I'm at 108 now, well I think so, the pixels have failed but that's a New Year job!

So have any of you come across this little weird problem? If it's not too serious, I'm more than happy to keep using manual as I am getting slightly more mpg than full auto and being honest with myself, it's just another lever/gadget to move around in the Starship Enterprise :)
 
weimieman said:
Here's a strange one guru's .....

What I thought might be a simple service problem (it wasn't), I've sort of stumbled across a temporary solution.

When in auto mode, when in top gear around 30 -40 mph, the engine would stumble at the same point in every cycle which I hoped would be plugs or timing but after a full service the problem remained. However, whilst playing around trying to tweak the most out of the mpg (yeah I know, dead horse and all that), I started playing around in manual mode and guess what, between 30 and 40 it's perfect. No stutter, no drop in revs - nothing. That kinda gets me paranoid that its an internal gearbox problem as I've heard so many horror stories about watching out for the box around 100K. I'm at 108 now, well I think so, the pixels have failed but that's a New Year job!

So have any of you come across this little weird problem? If it's not too serious, I'm more than happy to keep using manual as I am getting slightly more mpg than full auto and being honest with myself, it's just another lever/gadget to move around in the Starship Enterprise :)
Click to expand...
That is not a good sign....

This is a very common issue on the L322. The Torque Converter is controlled by the Gearbox ECU to limit slip to around 3%....

Now heres the kick with the Petrol V8's ZF box.....

In the box are a selection of clutches that engage and disengage in various patterns to give the gear selection.

They are lettered A - F.....and on 2 (I think) 'Towers' the first tower has clutches A, B and C and the second tower has D, E and F...

The clutch packs are sealed from each other using O rings....and they run against eachother using Roller bearings...

With me so far? :D

Now, the proble with the ZF box is the Roller bearing in i think the B clutch fails allowing the A Clutch pack to move slightly on the shaft, this movement prematurely wears the O ring that seals the A Clutch from the C Clutch (iirc) leading to reduced hydraulic pressure in the A Clutch and it starts to slip slightly...

Now the Torque Converter is told to try and limt Gearbox slip to 3% so the lock up clutch in the TQ starts to work overtime to limit the slip caused by the failing A Clutch.

This leads to extra wear in the TQ friction material, and can dump a lot of crap into the Gearbox fluid...this then acts like a fine cutting paste and can clog the filter leading to reduced hydraulic pressure, but can also contaminate the drive Clutch friction materials and cause the A clutch to slip further and a continuous cycle ensues....

Still with me???

First thing to do is to drain the Gearbox fluid and look at the condition of it, the magnets in the sump pan and change the Gearbox oil Filter....(use genuine Filtran Filter)

This will give a good indication of box condition as if the oil is burnt, full of drud and the magnets are covered in large metallic deposits (small fillings is normal) then it is an indication the box is on its way out.

Photos for your reference:

Missing Needles....

14Needlerollersmissing.jpg


15Looseneedles.jpg


Failed O Ring

16O-ringfailed.jpg


(Photos by Bemble/RRPhil)
 
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Oh dear ......

I don't know whether or not to thank you for such a detailed reply!!!! Is it considered polite to thank someone for depressing them:pound: Hey ho, such is the life of owning an L322 I suppose.

It sounds like I'm going to have to treat the old girl to a full service in my local Land Rover garage in the New Year as it sounds beyond my very helpful village garage sadly.

Looks like I'd better ask Santa for a reconditioned box or £3500 to help me out as I think my wallet's going to be crippled :crutch:

All joking aside though, thanks for a very detailed answer, much appreciated as always :)
 
I think my young Padawan may be being a bit alarmist there.

The signals from the turbine speed sensor and the output shaft speed sensor would tell the ECU immediately if any of the clutch packs were slipping and would drop the transmission into failsafe straight away. Both sensors are downstream of the torque converter so would be unaffected by anything going on with the torque converter’s lock-up clutch. The transmission ECU monitors the torque converter speed ratio via the turbine speed sensor and an engine speed signal that it borrows from the engine ECU from the crankshaft sensor, enabling it to modulate the LUC engagement pressure to keep the slip rate constant when operating in ‘continuous slip’ mode.

Your issue does, on the face of it, appear to relate to the LUC, especially as the engagement control map is different in automatic and manual modes. When mine went I was able to use my Faultmate to prove without doubt that this was where the fault lay.

Before:
TCLUC.jpg


After replacement :
NewConverter.jpg


LUC-AutomaticMode.jpg


A ‘properly’ remanufactured torque converter costs about £250 and takes around 5 hours to fit (the transmission assembly has to come out unfortunately) but the job requires no specialist knowledge of automatic transmissions so any mechanic that you trust (yourself maybe?) should be able to replace it. It’s also a great opportunity to replace the transmission fluid at the same time as all of the old fluid is removed rather than just the 5 litres or so when you drain and refill.

If you’re going to invest in some diagnostic kit anyway it would make sense to do this first and establish beyond doubt that your TC LUC is causing the problem (assuming of course that it has the capability to log the speed sensor signals like the Faultmate).
 
You really are a bit of a legend aren't you Phil ? :D:D:D

Many thanks for your correction...

So what is it that causes premature wear of the LUC, and the cause of the O Ring failure mode??
 
Wow that's fantastic thanks. The dark cloud above my head has lifted slightly:amen:

I'm a competent home mechanic but I think this is beyond me so I think it's manual mode until the New Year when my Landy garage can have a look.

I'll update the thread when I know more.

Thanks again.

Oh and don't be too hard on the Padewan, we all have to bow at the feet of the master some time :pound:
 
weimieman said:
Wow that's fantastic thanks. The dark cloud above my head has lifted slightly:amen:

I'm a competent home mechanic but I think this is beyond me so I think it's manual mode until the New Year when my Landy garage can have a look.

I'll update the thread when I know more.

Thanks again.

Oh and don't be too hard on the Padewan, we all have to bow at the feet of the master some time :pound:
Click to expand...
:D:D:D we are all learning all the time...:amen:
 
tomcat59alan said:
Bugger, I thought get the popcorn out and get comfy, here we go again but with a new duo.:D:D:D
Click to expand...
Nooooooo......Bemble/RRPhil is a legend with the ZF5HP gearboxes, I bow to his immense knowledge, heck, he rebuilds them as a hobby and for a very small profit to cover his time.....the man sits alongside the legend that is Storey Wilson as someone who is dedicating their free time from their day jobs to help us lesser mortals out.....
 
I dont have a L322 but its great to see that there will be really useful threads like this on LZ to help me out should my piggy bank allow some day lol
 
Saint.V8 said:
So what is it that causes premature wear of the LUC .....??
Click to expand...

I believe that the torque converter lock-up clutch wear issue is completely separate/independent of the 1058 202 016 axial bearing failure.

I started getting the ‘cattle grid’ noise with my L322 at around 100k miles. When I ‘unwelded’ the torque converter afterwards to investigate the cause (like you do) I could see that the friction plate was worn, but certainly not through to the backing plate, so I’m sure it could have soldiered on for a while longer.

Frictionplateclose.jpg


There had obviously been some stick-slip juddering taking place looking at the marking on the piston.

Chattermarks.jpg


My theory is that the lock-up clutch piston movement from on to off is only around 1mm so, once the friction plate has worn beyond a certain extent, the piston no longer has sufficient stroke left to enable it to control the slip speed accurately when operating in its ‘continuous slip’ mode.

TorqueconveterLUCsection.jpg

LUC piston in green, friction plate in red

Below around 20mph the LUC is fully off. Above 56 mph the LUC is locked solid. Between these speeds it slips at 3% (to absorb driveline torsional vibration as, unlike just about every other TC with a LUC on the planet, it doesn’t have a damper fitted) so I guess how quickly the LUC wears will depend on what proportion of the vehicle’s life is/has been spent between these two speeds at high load. Incidentally this 3% slip mode is the main reason ZF say that only LT71141 fluid should be used in the 5HP24, because the friction modifier pack used in this fluid was specifically developed around this requirement (still only lasts 100k miles though!)

I did see a post from someone (can’t remember which forum) who had left his LUC too long before having the torque converter replaced and it had worn right through the lining, so best not to leave it too long and risk having metallic debris floating around in the transmission.

ghurLUCfrictionplate2_zps3bfa21ff.jpg


Phil
 
Mine is still going strong after i had Sussex Autoparts refurbish the TC for me although you recall we changed some other bits and bobs while we were in there but the TC rumble was the annoying part and even after 110K miles the rest of the box was in pretty good shape.

When Sussex rebuilt it they commented on there not being much wrong with it but it was obviously enough for the cattle grid effect.

JPAT are the other main contender and are your preferred choice aren't they Phil ?
 
Bemble said:
I believe that the torque converter lock-up clutch wear issue is completely separate/independent of the 1058 202 016 axial bearing failure.

I started getting the ‘cattle grid’ noise with my L322 at around 100k miles. When I ‘unwelded’ the torque converter afterwards to investigate the cause (like you do) I could see that the friction plate was worn, but certainly not through to the backing plate, so I’m sure it could have soldiered on for a while longer.



There had obviously been some stick-slip juddering taking place looking at the marking on the piston.



My theory is that the lock-up clutch piston movement from on to off is only around 1mm so, once the friction plate has worn beyond a certain extent, the piston no longer has sufficient stroke left to enable it to control the slip speed accurately when operating in its ‘continuous slip’ mode.


LUC piston in green, friction plate in red

Below around 20mph the LUC is fully off. Above 56 mph the LUC is locked solid. Between these speeds it slips at 3% (to absorb driveline torsional vibration as, unlike just about every other TC with a LUC on the planet, it doesn’t have a damper fitted) so I guess how quickly the LUC wears will depend on what proportion of the vehicle’s life is/has been spent between these two speeds at high load. Incidentally this 3% slip mode is the main reason ZF say that only LT71141 fluid should be used in the 5HP24, because the friction modifier pack used in this fluid was specifically developed around this requirement (still only lasts 100k miles though!)

I did see a post from someone (can’t remember which forum) who had left his LUC too long before having the torque converter replaced and it had worn right through the lining, so best not to leave it too long and risk having metallic debris floating around in the transmission.



Phil
Click to expand...

Cheers Phil, see this is why you are a legend....

I will revise my advice from this point on!
 
holidaychicken said:
JPAT are the other main contender and are your preferred choice aren't they Phil ?
Click to expand...

Yes, I’ve used JPAT for several years now and I get a good discount from them, but I’ve also used Sussex Auto Parts and they’ve been fine too. I’ve seen plenty of people on the forums saying good things about Mackie’s in Glasgow too, so that’s three out of the total of only seven ZF official parts suppliers in the UK. Here’s the full list :

John Mackie Automatic Transmissions
95 Causewayside Street
Tollcross
Glasgow G32 8LT
Tel: 0141 778 4545
Fax: 0141 778 4476
www.mackie-transmission.com

Alliance Automatic Company
3 The Pilton Estate
Pitlake
West Croydon CR0 3RY
Tel: 0208 680 6802
Fax: 0208 686 3381

J P (Automatic Transmissions) Ltd
Units 4a & 4b Pear Tree Industrial Estate
Upper Langford
N Somerset BS40 5DJ
Tel: 01934 852 772
Fax: 01934 852 211
http://www.jpat.co.uk

Sussex Auto Parts Ltd
Units 40-44
Station Road Industrial Estate
Hailsham
Sussex BN27 2EY
Tel: 01323 848 886
http://www.sussexautos.co.uk

Auto Suppliers Ltd
Edwin Avenue
Hoo Farm Industrial Estate
Kidderminster
Worcestershire DY11 7RA
Tel: 01562 865577
Fax: 01562 865588
http://www.autosuppliers.co.uk

Automatic Choice Ltd
ACL House
Coombend
Radstock BA3 3AS
Tel: 01761 436688
www.automaticchoice.com

Vanmatic Ltd
1 Viveash Close
Hayes
Middlesex UB3 4RY
Tel: 0208 8489911
www.vmtp.com

I’ve left off Motorsport Transmissions in Cumbria because they’re a ZF manual transmission specialist
 
Think that's got them covered !

Sussex have been pretty handy at times when i had to buy minimum quantity of parts from JPAT, hark at me, handy at times, like i have ever had my hands inside more than one transmission and ever intend to do it again if i can help it, although very enjoyable once the thing is out of the car

i have just had a very good quote from JPAT for my transfer box chain which i think is a bit stretched and half the price of Sussex, as long as its BorgWarner.

i was having a search across the net last night to see if you have ever done a write up on stripping down the NV225, i found your other strip down and youtube vid but have you stripped one of these out of interest?

( apologies OP, my high jack is only temporary :eek: )
 
I just wanted to say thanks for all the detailed replies and knowledge you've passed on to me on this topic. Believe it or not, I've printed it all out for the village garage at their request and they're going to have a look at it on Friday for me so hopefully I won't need to visit my indy Landy garage in the new year.

Thanks again all, I love this forum and I love Landy people. Must be why this is my 8th one.

Scott

PS Might be my 8th but it's also my scariest :crazy:
 
weimieman said:
I just wanted to say thanks for all the detailed replies and knowledge you've passed on to me on this topic. Believe it or not, I've printed it all out for the village garage at their request and they're going to have a look at it on Friday for me so hopefully I won't need to visit my indy Landy garage in the new year.

Thanks again all, I love this forum and I love Landy people. Must be why this is my 8th one.

Scott

PS Might be my 8th but it's also my scariest :crazy:
Click to expand...
LZ is the best Landy forum on the net....decent blokes with a wealth of knowledge...and fecking good sense of humour too.....

The L322 can be scary...but at the end of the day there is somuch info around about these cars and the Bimmers it is based on so there is bound to be something that will help!!
 
Quick update all. My local garage did a quick service on my gearbox last friday including a full flush and filled it with the priciest oil they could find (apparently they went on this forum as I printed out Bembles conversation and found out the best oil to use) and it did seem to make a difference ....... for a little while. The juddering was slightly better and then yesterday it decided to throw all the toys out of it's pram and judder for Britain around the 30 mph mark. Whereas the previous judder was more of a little stutter, yesterday's episode was more like trying to make a milkshake in the driver's seat! Ah well, never mind, it's back to manual mode for me until the sufficient conkers can be saved for the torque thingy rebuild Bemble mentioned. Wish I'd picked up on all this during the 30 day warranty but hindsight is a wonderful thing so they say. I suppose all this is taking my mind off waiting for my all comms to arrive from the States :)
 
weimieman said:
Quick update all. My local garage did a quick service on my gearbox last friday including a full flush and filled it with the priciest oil they could find (apparently they went on this forum as I printed out Bembles conversation and found out the best oil to use) and it did seem to make a difference ....... for a little while. The juddering was slightly better and then yesterday it decided to throw all the toys out of it's pram and judder for Britain around the 30 mph mark. Whereas the previous judder was more of a little stutter, yesterday's episode was more like trying to make a milkshake in the driver's seat! Ah well, never mind, it's back to manual mode for me until the sufficient conkers can be saved for the torque thingy rebuild Bemble mentioned. Wish I'd picked up on all this during the 30 day warranty but hindsight is a wonderful thing so they say. I suppose all this is taking my mind off waiting for my all comms to arrive from the States :)
Click to expand...
I would not have advocated a full flush of the gearbox....

Gearbox Fluid is a very good detergent....currently inside the box hidden in harmless nooks and crannies is a build up of debris....harmlessly sitting out of the way doing no bother!

When you only change the sump contents during a 'normal' fluid change, you change about 65% or so of the original fluid, the rest sits in the Torque Converter.

You then refill with clean fluid - diluting the remaining 35% or so.

This dilution of the clean fluid, slows down the detergent effect.

NOW....

If you mega flush and take all the old fluid out and replace with new, it will start to strip clean the gearbox, and pull all that accumulated debris into the oil and box, which can cause grief.

It is known as New Fluid Syndrome (or something similar)....

Some get away with it, and some have reported it has trashed the box requiring a rebuild due to contamination!

The dilution method will disturb some of the harmless crud into the oil, but the second flush will start clearing this out before it has a chance to wreck everything!
 
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