Auto box problems td4

Hi all my x reg td4 has started messing about,once engine has got warm the gearbox drops back to 4th and revs up,until you let foot off then drops back in 5th again.all other gears are ok.been told today that it is possibly clutch pack housin cracked.quoted on bourd repaire £800 or new box £1750 any advise thanks

does it show any fault codes?

Hi no faults showing on dash

before you go and spend all your money on having it rebuilt, try having the auto fluid changed. shouldn't cost more than £50, and might just make a difference.

was getting funny changes on mine a couple of years ago, had the fluid changed and cured it.

also, be wary of imagining you have a fault when in 5th. The gearbox has a torque convertor lock in it, so when you are cruising at a reasonably constant speed, the torque convertor locks up so there is no slip. If you give it a small increase in throttle, the torque convertor unlocks, so the revs momentarily increase. I was convinced mine was slipping, but the mechanic told me it was normal.

good luck

Hi thanks for that,oil has been changed,but when it goes back to 4th the car slows down,especialy if you on a slip road you think you are going to stop so quite bad now.