Torque converter taking a while to lock up properly

I popped via the garage on the way home. The Landy took 1.25 litres of ATF!

Gear changes already seem smoother! Tomorrow will show whether the lock-up clutch problem has gone away! Let's hope so.

This morning, all seems to be well. Let's hope it stays that way!

Well done fishsponge ... your a winner :clap2:

If you're not being sarcastic, thank you very much!

If you are being sarcastic, that's hilarious!

another question... what's the difference between measuring automatic transmission fluid when warm vs cold?

It's supposed to be measured when cold, but why? Surely after a long run (when all the oil is definitely up where it needs to be) is going to be better than having just started the engine, been into 1, R and then N again...

Unless the engine's been running a while, surely some of the oil still might not have reached where it needs to be, thereby giving a reading higher than it really is?

Some gearbox levels can be checked Hot and the dip stick has the markings for Hot and Cold marked on them, but not Land Rover with the RRC or disco 1 it's Cold for them.

OK, thanks for that. Cold it is.

I'd have thought the fluid got "bigger" when it was hotter, but if that's the case, it certainly should have still be showing on the dipstick after my 30 minute journey to work this morning, but sadly, when I got to work and checked the levels (while hot), there was nothing on the dipstick whatsoever.

I'll disregard that reading though, and take it again in the morning.

The weird thing is that taking a reading even when cold appears to be quite difficult. With engine oil, it's easy. The dipstick is clean until the oil touches it at which point it goes black and it's very clear where the oil comes up to as there's a definite clear oil level on the dipstick.

With the ATF though, i'm not finding it as easy. Obviousy, the fluid is different, but it's almost as if there's a splattering of ATF in the dipstick tube itself, so when I pull the ATF dipstick out there's a light covering of ATF several inches up from the maximum point, but there's no clear definite fluid level visible.

It's almost as if I haven't cleaned the dipstick before inserting it again to take a reading. If i clean it and put it back in, it just comes out as if i haven't cleaned it again, so it's very hard to read.

Unless, of course, it's so damn empty, that the clear definite fluid level is something i've not yet seen and so don't know what it looks like!

The other alternative is that it's massively overfull, but I very much doubt it. Since putting in 1.25 litres last night, gear changes have been much smoother, but although the lock-up clutch engaged perfectly for my journey to work, it sadly did not on the way home.

So who knows what the hell's going on. I'm going back to the garage tomorrow morning, but I'm rather concerned that they might just keep putting ATF in until they see a clear level on the dipstick, but if it just keeps coming out covered in a light splattering of oil, we may end up overfilling it.

I suspect I'm worrying too much, but knowing nothing about automatic gearboxes I've no idea whether getting this wrong is disastrous or not! I have the Haynes manual, but the procedure for checking ATF levels in there is subtly different from what everyone else says!

There is a definite line but as ATF is very thin and I find it does need a bit of light to see the line, if I keep dipping then I have found that the remaining oil in the tube and maybe the gearbox insides turning over does confuse things sometimes.
So just dip once, I will look in my Haynes and see what they say.
As u know there's not much to it, move the selector from P to 1 and back to N or P and with the engine still running go and remove the dip stick, you may have to wipe it and dip it to see the fluid level and you should see a line, as you do with engine oil.

Checked it again this morning, and i've put another litre in, so that's 2.25 litres i've put into it now! The dipstick now looks perfect

I've checked the entire underside of the vehicle (had it up on the ramps today for wheel "geometry") and there's no sign of fluid leaking from anywhere.

I've asked the garage that previously serviced it to tell me when the ATF level was last checked, and they're going to get back to me on Monday.

Failing that, I guess i'll just keep an eye on it... i'd love to know where it's all going though!

If you don't have a leak who knows where it went, maybe the fluid was drained at a service and wasn't replaced with the correct amount around of 4.5 to 5 litres so only used 2.5 litres and forgot the rest.

right.... an update!!

Since all the topping up of ATF, the level is still fine. It has not lost any, and what is in there still looks as it should and smells as it should.

It changes gear very smoothly, pulls well, kicks down when it should and drives essentially perfectly.

BUT...

The torque converter still doesn't like locking up early on in any journey. Doesn't matter whether the weather is hot or cold... but for the first few miles of a journey, the torque converter is very reluctant to lock above 50mph.

What I now do every morning and night (on my daily commute) is drive above 50mph until it tries to lock but fails, then slow down to 48mph, then go above 50 again until it tries to lock, then slow down again, speed up, slow down, speed up, slow down, etc, etc, etc... until it locks up properly and I then accelerate up to cruising speed of 60mph and stay there!

For the rest of the journey is then unlocks and locks up happily as I go above and below 50mph or so (most of the time, anyway!).

I phoned Ashcroft and they think it might be the "valve block" that's knackered. I've not changed the ATF filter yet, but could that really cause this problem?!?

Advice, please!! It's becoming rather frustrating...

Well it certainly sounds as though a complete drain and filter change wouldnt hurt.As James has pointed out in another thread,the ATF is a detergent,so it will have been cleaning things as it circulates.Seeing the state of the fluid that comes out will give you some pointers about the state of the working and tell you if there are any loose particles floating about.Have a good look at the filter that comes out,too - see if there is anything caught in it.If the box WAS that low on fluid and running a long time that way,there MAY be some extra wear somewhere.Also,a partially blocked filter would certainly inhibit the free flow of the ATF and make a "charge" unpredictable.It sounds like the box works better as it gets hot,I would think that hot fluid would run thinner and easier,so yes,I reckon a bad filter could contribute or even cause the problem.But theres people who are more experienced than me who have yet to weigh in.

The price of the fluid and filter is not massive and having new would certainly give you a clean sheet to work from as well as what you see from the stuff coming out.Theres stuff in other threads recently about how much fluid is retained during changes and how much to put in and how,worth a read.

One thing,sounds stupid,but it got me.I spent days looking at a transmission dipstick,seeing no fluid level,wiping it,dipping again ,running engine in P or N,seeing no fluid,doing it again.Then I looked at THE OTHER SIDE OF THE DIPSTICK......where there was a clear level.Doh !!!!

yeah, i had that dipstick problem too! lol, thanks for the advice also.

Doesn't part of the chassis have to be unbolted and bashed out of the way to change the filter in an auto box in a 300TDi disco??

it is more likely sticking valve that frees when hot there is a lock up regulator bolted to valve block ill see if i can find a piccy but havent learnt how to download one myself

hmm... do you think a filter and ATF change might help then, or could Ashcroft be correct in that I need a new valve block??

you wont want new valve block if everything else works fine ,either control mechanism or clutch in t/c since it does work properly for most of time and seems temp sensitive i wouldnt think clutch ,valve block would cost a few pennies,oil change may help if not done for a while,since yours seeme to be very specific it might be worth looking at specific valves which i will try and get some info for you to work with

OK, so the consensus seems to be to do an oil and filter change... i'll start trying to figure out how to do that soon. I think the Haynes manual suggests i take it to a garage because it's too complicated annoyingly, but I remember someone else telling me it's really quite simple!

As for looking at specific valves, how easy is it to change a single valve? does the gearbox need to come out?

...and is there a diagram anywhere so I can see how it all actually works? I understand the concepts of two-way piston-type valves etc... but this gearbox specifically I have no idea about in detail.

oil and filter is messy but not complicated,you cant change a valve,they are spool valves machined to housing ,you can swap assemblies / remove clean,i had an old rebuild book but ithink some explanation is given in rave

ok, so basically i should change the oil and filter.

if that doesn't help i'll either need a new valve block or will need to clean the existing one.

Is it difficult to remove the valve block? How long should it take to remove, clean and replace a valve block having, say, just arrived home in the vehicle...

The gearbox does not lock up until the fluid has got up to temperature - I leave Wantage and drive to Didcot, about 6 miles, and it frequently doesn't lock up. I did a google and found Discovery II Transmission and Transfer Case  MuddyOval.com, which explains what is going on. It mentions lockup in all gears, but I think that was changed for production - the workshop manual says lock-up in 3rd and 4th only.

Cheers!