Hello, I have now fixed the issue with holding gears by replacing Radiator, gearbox cooler and changing the gearbox oil and filter. However I still have the issue at slow speeds(coasting up to junction/roundabout) when applying power I’m getting a thud in the back, I can avoid this by been gentle with the throttle or using manual mode. It’s almost as if the box panics then finds its gear. Only happens after about 30m driving. Any ideas what this could be? Thanks.

Which engine/gearbox is it?
These are the symptoms for a ZF 5HP which needs adaptations reset.

Sorry I forgot to put it. It’s a 2004 BMW 4.4 V8. I searched about that as it seems more common on the X5s. People seem to say you can’t reset the adaptations on an old box though, then surely that means the only option is a new box? Thanks again.

I seem to recall that there have been some threads about this, particularly RRPhil, its a 1st to second gear issue I think.

We have a similar thging on our 2004 4.4V8 with the ZF box, into reverse, if you stop the car then select reverse without waiting a couple of seconds, it goes in with a bit of a thump! We had the gearbox totally rebuilt a couple of years ago and new radiator, trans oil cooler etc, but we still get the same thing.

It’s tricky to determine if this is a control issue or a mechanical/hydraulic fault. One option: I could supply you with a fully rebuilt and tested valve body assembly for £300 +VAT +postage to try. If this didn’t fix the issue you could return it within a fortnight for a full refund (except the postage charge) and you would then know that you have an issue with the running gear which requires a transmission rebuild to fix. Even if it did fix the issue, you still have the option to return it if you fancied having a go at rebuilding your own valve body assembly, knowing that’s where the problem lay.

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That’s great info thanks Phil,. To be honest I’m struggling to find somewhere round here that knows anything about these 4.4 gearboxes only the TD6. That would be beyond my abilities to try.
Do you have a workshop I could bring it to? Many thanks again for detailed reply. I have been quoted about £2000 for a new box and TC. Im wondering if that might end up the cheapest option rather than paying someone to investigate if I’m unable to carry out the work myself. Thanks.

Unfortunately, I only work on the transmissions themselves as I don’t have the facilities to work on vehicles.

Replacing the valve body assembly is simply a matter of removing the sump pan (22-off T27 10Nm), then the filter (2-off T27 5Nm), then the two speed sensors (1-off T27 8Nm, each) then undoing 22 bolts (T27 8-10Nm) and releasing the wiring loom connector and it drops right out. There are no gaskets or seals to worry about between the casing and the valve body. In fact it’s so simple that Land Rover allow their mechanics to do it, and it’s covered in RAVE. The book time for removal and refitting is 1.7 hours. Any competent person can do it and there is absolutely no specialist knowledge of automatic transmissions required.

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