Automatic gearbox dropping into neutral

[Lewiss67]

2003 VW Caravelle (T4) 2.5tdi Automatic

Recently , the last couple of months or so my T4 2.5tdi auto box has been jumping out of gear when cold. It doesn't always happen , seems to be completely random , but sometimes after I start her up and head off down the road she will jump out of gear , rev up and then drop back into gear violently. I've got use to it now and let off the revs until she goes back into gear , avoiding any nasty jolts. It mostly happens after driving over speed bumps and accelerating again (my work has a lot of speed bumps). But after I get her up the road and warmed up she never does it again....

My only though is to check the gearbox oil level , which I hope to do in the next couple of days. But apart from that I have no clue...

Vans only done 63k miles so a little worried why it would be playing up like this. Checked the web but couldn't find much so that brought me here.

Any help would be greatly appreciated , hope to get a rough idea of what the problem is so I can go about solving it myself, if not I guess I'll have to take it to a mechanic...

Again , any advice would be great

[TheEnd]

It does sound like low fluid, and it is best described as losing drive rather than falling out of gear.

What could be happening is it is running out of fluid to actuate some parts with hydraulic pressure until is sloshes back to the pickup and then it connects again giving the kick.

[Lewiss67]

I just can't get my head around that after a couple of minutes driving it doesn't loose drive at all, ever.

I guess that when the oil warms up it moves around the box more freely eliminating the loss of drive????

Been looking at how to top up/ change the oil in the box , looks like a right pain :/ should have stuck with a manual haha

[TheEnd]

Liquids do expand with heat, so they might be part of it, although I could be barking up the wrong tree.

It does fit with losing driver after a bump in the road, or acceleration which can slosh the fluid away from a pickup.

If there is an autobox fluid dipstick, you can check it with that. You might need to top up through the dipstick too if there isn't a dedicated filler.

If there isn't a dipstick then it can get more awkward. Some have a filler and drain plug on the autobox sump, and the fill level is just when it stops overflowing on the filler plug when it is up to temp and has been cycled through the gears a few times.

Those filler plugs on a gearbox are usually tight to get to, and need to have fluid pumped in with a hand pump.

[PaulKemp]

On a V6 Galaxy that had a VW auto box you had to measure and top up warm again due to fluid expansion.
Once it started playing up just topping up only delayed a rebuild

[paintman]

FWIW the ZF box as used on Land Rovers etc can play up when cold but normal operation returns after its warmed up & the usual cause - assuming correct fluid level - is a partially blocked filter screen.
I have no idea whether this is relevant to your box, but it's something else to consider.

[PositronicRay]

I'd change the fluid, filter and hope it does the trick.

[Sardonicus]

I agree with The End on this transmission fluid expands when it gets hot so that would explain loosing drive only when cold, as suggested if its been run this low I would service the gearbox unless you want big bills later on less fluid runs hotter and wears out quicker

[Gnaude]

Hi, I am facing the exact same issue. VW Caravelle 2.5 TDI - Automatic. I had the complete gearbox, torque converted and valve box refurbished but the problem persist. Seems also to be only when the car is cold also also at speed humps or stop and go. Were you able to resolve your issue at per previous post ?
Thanks in advance.

[tr7v8]

Generally auto boxes have two levels on the dipstick for hot & cold. ATF expands quite a bit when warm & that is why it is OK when it is hot.
At that mileage I'd be doing a filter & fluid change anyway.
Do not keep driving it until it is sorted. The banging into gear will break clutches & potentially other bits within the box, that will be £££££££'s
Find out the process for doing a fluid & filter change, some are easy, others these days can be a PITA.

[Gnaude]

Thanks. I also read that you get the right and wrong gearbox fluid. What transmission fluid should i use ? Thanks

[Vampydm]

I have the same problem, we top it up with 2 litres of transmission fluid, it warmed there for a week and it’s doing it again specially when it’s cold. Also feels like lack of power when driving it. Now, it seems to me it’s more like a wire or sensor, as if I switch it off for a couple of seconds and switch on again the gear comes back into position...

I heard the wire loom gives problem as it is attached underneath of the rotators and not chasis and the vibration breaks them...

Have anyone changed it? Or have sorted the problem??

[scoobydo123]

Could be solenoid issue. Don't know the specific vehicle but normally there is a diagnostic procedure assuming you have a TCU. Failing that could be an issue with the valve body. Also important when checking levels is that it is up to temp and you cycle thru the gears via the lever stopping on neutral normally is when you read the stick but refer to manual.