XSeries-forum

I am having issues where my X5 gearbox starts to play up when it heats up, i have given it a new filter and a change of oil and it has made no difference, so before i go and through another gearbox into it I was hoping someone may be able to shed some light on what may may going wrong.

Driving from cold it runs great, changes gears with no issues, when it warms up it starts holding the gears a little longer than it should and ultimately it eventually loses gears and through up the dash warning light.

I can switch it off and it all works again for a while before it will ultimately do the same again.

I have tried driving it in manual mode, now if i keep it in M4 or lower it runs well and does not lose gears, also if i drive it in sports box it seems to work better and although it still holds the gears a little too long it does not seem to throw a wobbly and lose gears.

It did get a stage 1 remap a while back, the gearbox issue was not present until after this so i had it taken back off to see if it solved the issue however it still had the issues so put the stage 1 back on.

The car has now done 204k, it has extensive and FSH, no previous gearbox oil changes notes and the filter removed was the original one going by the date on the filter when i removed it to change it.

It is throwing up 'tcm 4f85 egs ratio monitoring clutch e' fault, when scanned, although when i scanned it today a load of other historical codes which i have cleared down and will recheck in a few days.

When it plays up when driving the gears are lost and the dash states gearbox failure, still safe to drive.

I have just reset the gearbox yesterday with my Mac Tools Machine to relearn, as of yet i have not driven it far enough for it to warm up enough to develop the fault, it can take a while before it throws the fault up and is always when it is warmed up sufficiently.

Would anyone have any ideas on a fix for this, before i go and order another box?

Thanks in Advance...

Hello &

ZF 6-speed transmission?

It sounds like the 'E' clutch is slipping. If the error codes come back then it very likely needs a transmission service for that clutch pack, and if doing that then a full rebuild is on the cards as it will all be in bits to do that anyway. Some remappers forget about the max torque that the box can take and if exceeded then the clutches are overloaded and slip. Being 'wet-multiplate' once that happens then the damage is done.

At 204k miles the transmission has done pretty well really. My E53 with the 1st Gen 6-sp box didn't even make 40k!! The 2nd gen (what you should have) is much more reliable though.

Hi,

Yes it is the ZF 6-speed transmission.

I suppose my only concern is if the gearbox is rebuilt , would the fact that the car has had a stage 1 mean that the the gearbox is likely to fail again, the increase was minimal at around 10% in BHP.

It might just be that the box was worn anyway and either really bad timing or awful coincidence and nothing to do with the remap. 10% isn’t a lot and unlikely to push a rebuilt box ‘out of limit’. A worn box is another matter though.

If it’s had a proper rebuild - all clutch & brake packs, serviced the servos in the Mechatronics Unit (gearbox mechanical brain), gaskets, seals etc, and a new TC it should be like new. Decent rebuilds come with 12 month warranty too, often unlimited mileage. Still looking at around £2k for a decent one. Much less and it may not have been remanufactured, just peered at

Gearbox worn out the extra torque of a remap has just made the fault appear quicker once rebuilt will be able to cope no bother

OK, thanks for the feedback, i will get some quotes online to see what it will cost me.

Not sure if it will help, but there are two close to me. Biggleswade (A1 Premier Transmissions) and Letchworth (Herts & Beds Transmissions). Both will collect too. About 30 miles north of London just off the A1. Both have positive feedback from members on here. Might be too far away for you though.

Thanks i will give them a try.