X308 Gearbox - yes that old chestnut!

[fast cars]

My 3.2 V8 2000 car has a habit if giving an initial jolt from stand still, its almost like the rpm and pressure need to build before it takes off, also the same when going into reverse, just needs a little rpm before it engages. Other wise it works to perfection, smooth changes and quiet, no vibration.

I'm looking for any ideas from anyone out there if this is something that can be fixed with new oil and filters (wishful) as doubt its ever been done being a 'sealed jaguar box' or is it all together something more sinister??

Cheers

D

[GavinPearson]

It's oil level. Reverse works on the B clutch which is what the transmission defaults to when the A clutch / drum fails.

You only need to top the oil up, not change it. You do need to have the oil set at the right temperature though, or you won't fix the problem, especially when cold.

My transmission had the A drum fail, I rebuilt the unit. Every single clutch and disc was perfect, even though the oil had 106K on it.

[melhookv12]

Check your oil level first. Or get it checked.

[GavinPearson]

Zulu 10 said:

GavinPearson said:

My transmission had the A drum fail, I rebuilt the unit. Every single clutch and disc was perfect, even though the oil had 106K on it.

That’s very interesting. Mine has only done 44,000 miles and I changed fluid and filter at 30,000 ish.
I’m mulling various options:
Take a holiday in Germany and get the car to a ZF Service Centre to have a valve block rebuild – using the latest spec components. (That will hopefully show if the valve body may have damaged the A Drum), or;
Buy a cheap second hand 5HP24 on EBay and rebuild it myself and fit it in place of current box, or;
Buy a cheap second hand 5HP24 on EBay, swap it for my existing box and then rebuild my existing box, then swap back,or;
Forget about the whole thing as the car only does 5,000 miles/year.

The issue with the last option is that we use the car for two European holidays each year, and not a lot else – it even has LHD headlamps permanently fitted – and I’m worried about spoiling a holiday if the box did fail.

I’d be interested to know what skill level you think is required to rebuild the box – I’ve got a well equipped workshop and have built numerous engines over the years, but never done a gearbox.

I would do nothing, it isn't broken so don't try to fix it.

I say that as a former Transmission Engineer who has engineered them for a living.

If you have a good workshop then it might be an interesting exercise for you to strip and rebuild a transmission, the big issue is getting debris out of the torque converter though.