Torque Converter problem?

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Originally Posted by Titch101

Blknight would you have any idea what would cause an autobox to play up only on the changes from 1st-2nd (holds 1st too long) and 2nd-3rd (revs flare)? 3rd and 4th change and lockup smoothly. It's a lot more obvious under heavy load.
Fluid and filter recently changed and MAF is working as normal according to the Nanocom an no fault codes logged.

Mechanical or Electrical ?? Maybe governer or valve block??

Would appreciate your opinion.

Cheers,

Rob

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Well when that happened to me (sticking in 1st and not changing up) at 250k km, it turned out to be a failed bearing in the TC, which spread metal flakes throughout the transmission. $3700 later new rebuilt transmission.
Aparently TD5s are hard on the auto - torsional vibration?
I reckon changing the TC at about 200k km could be a good proactive investment.

Terry

Hoping it's not a total rebuild job, the oil I changed out was pretty clean and no obvious metal shards in the pan or glitter in the oil.
What would a tentative gbox overhaul set me back if I get some bad news on Monday?

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Originally Posted by Pinelli

There's no actual auto fluid temp sensor, so the computer sort of guesses when it is hot enough based on coolant or outside temp, and time the engine has been running so I don't think that's a temperature thing. How long since you e changed the auto fluid?

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About an hour ago :) . I brought the disco broken , blown head gasket , about 8,000Km ago . So know idea when anything was last done . Just draining the sump netted about 3 1/4 ltr's of near black fluid , I guess this is what is referred to as burnt . After changing the filter I got 4 ltr's back in , I thought this was a little on the light side . But checking after a run around the block its still coming out the bung ( what a stupid idea , still only one burn on the arm ) .

Take it for a good spin tomorrow and see if its any better .

Chris

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Originally Posted by Chris77

...........Just draining the sump netted about 3 1/4 ltr's of near black fluid , I guess this is what is referred to as burnt......

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I think the more accurate term is screwed!

Walking out to the garage this morning with the intention for going for a drive only to find a large puddle of trans fluid under the disco :( . Stupid sump seal , must have knocked it as I put it up . So dumped another 4ltrs of fluid and relocated the seal . Several hours later I get it out for a spin and after a while , just as I was loosing all hope , the lock up kicked in and held :) . Went for a 50 odd km drive and it is locking up just fine at 85 ish kph and holds with a good boot full of gas right up until the kick down comes in .
So I think I was very lucky . Not sure how long it will last as I thought I would have done some damage elsewhere , ie buggered the clutch .

I still think the torque converter slips to high , I read the info on how they work off the other link from blknight and see its say a converter should slip until peek power . I don't see why thou , the way it is now the torque converter is still slipping when the box hooks another gear . If it was not slipping you would not need to hook the next gear . Also in a manual you don't slip the clutch until 2700rpm and manual disco's get around just fine . So I will look into pricing up an ashcroft t/c to chuck in it at some stage soon .


In short my problem was at 100kph any slight increase in throttle caused an increase in engine rpm but no significant increase in road speed ( torque converter lock up not locked or slipping ) . I changed the filters and only drained the auto sump ( did not flush cooler etc ) and replaced the fluid .The fluid was black . At this stage the lock up now holds , I will post if it craps out in the next few weeks .

Cheers
Chris

Chris ... I'd be (and did after I bought my D2a and drained/refilled the auto) driving it for a few hundred k's and changing the fluid again .... and then again after another 500-1000km ... if it was as bad as you say when drained, you only get less than half the total fluid out each time you drain it, so you've still got more than half the old fluid still in there.

Drain and refill another two times if the auto appears to be working OK.

my 0.02c :)

Ditto that. If you're keen, the auto sump from a D1 (and some other LR models too) fits the D2 and it has a dipstick. Let's you keep an eye on it and top up as required. No more trying pump oil in with the ungine running.
Just be warned, the D1 has a crossmember running under the sump, and the V8 exhaust also runs under the auto sump.

Took my local wrecker 3 hrs to get the sump off the V8 D1 they had, and 15 mins for me to swap it over on the D2 TD5 :)

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Originally Posted by OffTrack

Dave,

Is it possible to assess the level of wear from the gearbox adaptation values reported by diagnostic tools. There is very little documentation I can find that explains what values might indicate excessive wear.

cheers
Paul

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realistically no, however. If you have the full list of its adaption pattern from the day the box was built till now, most people dont so generally its not achievable

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Originally Posted by Chris77

About an hour ago :) . I brought the disco broken , blown head gasket , about 8,000Km ago . So know idea when anything was last done . Just draining the sump netted about 3 1/4 ltr's of near black fluid , I guess this is what is referred to as burnt . After changing the filter I got 4 ltr's back in , I thought this was a little on the light side . But checking after a run around the block its still coming out the bung ( what a stupid idea , still only one burn on the arm ) .

Take it for a good spin tomorrow and see if its any better .

Chris

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if you only change the pan oil and dont flush it thats not far off. That oils not burnt its a non swear filter friendly word.

Quote:

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Originally Posted by Chris77

Walking out to the garage this morning with the intention for going for a drive only to find a large puddle of trans fluid under the disco :( . Stupid sump seal , must have knocked it as I put it up . So dumped another 4ltrs of fluid and relocated the seal . Several hours later I get it out for a spin and after a while , just as I was loosing all hope , the lock up kicked in and held :) . Went for a 50 odd km drive and it is locking up just fine at 85 ish kph and holds with a good boot full of gas right up until the kick down comes in .
So I think I was very lucky . Not sure how long it will last as I thought I would have done some damage elsewhere , ie buggered the clutch .

I still think the torque converter slips to high , I read the info on how they work off the other link from blknight and see its say a converter should slip until peek power . I don't see why thou , the way it is now the torque converter is still slipping when the box hooks another gear . If it was not slipping you would not need to hook the next gear . Also in a manual you don't slip the clutch until 2700rpm and manual disco's get around just fine . So I will look into pricing up an ashcroft t/c to chuck in it at some stage soon .


In short my problem was at 100kph any slight increase in throttle caused an increase in engine rpm but no significant increase in road speed ( torque converter lock up not locked or slipping ) . I changed the filters and only drained the auto sump ( did not flush cooler etc ) and replaced the fluid .The fluid was black . At this stage the lock up now holds , I will post if it craps out in the next few weeks .

Cheers
Chris

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Where the TC achieves fluid coupling can be varied for many things, the example of slipping till peak power is where you want it when you want max twist at the wheels and care little for anything else fuel economy and mechanical sympathy for the rest of the driveline being 2.

IMHO the TC coupling point is a good compromise for economy power to the wheels and driveability both on and off road. I think the biggest improvement that could be made to the electronic hp22's is fitting of a manual control to the TC lockup clutch.

The other option for a dipstick on the D2 is the thread in the D2 sump is metric and there is an adaptor available that will screw in to it and also fit the tapered (JIC) fitting on the dip stick tube. I just need to find a dipstick and tube.

Well its been a couple of months and I forgot to post how I got on with the auto . After a half pie fluid change it hopped in and out of torque lock up like I think it should for about 3 weeks . Then it slowly got worse . However I have figured out how to get it in , once its warmed up and accelerating past 80 km/h lighly on the gas , it will lock in . If it does not go in as its accelerating past 83 ish it will not go in at all . Slow down and try again and I can usually get it in .

From cold the auto will not go into top gear until it has warmed up a bit ( normal ) , however I can't get the torque converter locked up until it has warmed up well past this point . Also to throw a spanner in the works I noticed the other day that when towing a heavier trailer than normal ( only around 800-1000kg ) it goes in just fine all the time I expect it to , with no stuffing around of the throttle . The only thing I can think of is the auto is warmer than normal driving .

So why does my tq converter not go in until its hot ? Does the cooler have a thermostat/bypass ?

Keep meaning to get a full flush done on it but have not got around to it yet .

Cheers
Chris