ML270 gearbox playing up

[Matthew Hall]

For sometime and normally in winter the gearbox stuck in 1st gear. Stopping and re-starting the engine would cure it for that journey. We drove to Italy this year and the Perugia MB garage said the problem was the battery which we changed. That problem seems to have been solved but on the way back the gearbox started to over-rev in 3rd gear. Since coming back the over-reving seems to have gone away but lately the box has not been changing down automatically when accelerating up hills but will if you manually select a lower gear. Any thoughts on what seems to be a series of faults? Up until now the box has been flawless. The car has done 130k miles and has been serviced by MB since new.

 

[psmart]

Mine locked in Park during winter (sub -20'c) and you had to run the engine for about 30 minutes before it would go into drive. A couple of times it locked into 1st again due to the cold. The Indy determined it was lack of oil and once he'd topped it up, it was fine.

1st measure, get the oil level checked.

ps) Welcome to the Forum, quite a few ML owners on here as well as engineers etc

 

[kebo57]

Hi Mat loads of thread on the ML 270 auto box you said

"The car has done 130k miles and has been serviced by MB since new"

This doesn’t mean that the auto box oil has been changed even if it has you can only change around 5 lts out of the 8 lts that the box holds,

Its difficult to advise but my ML has done 195,000 miles & I have put about 15 lts through the box in the last 50,000 miles when you see the colour of the oil you will under stand why
Like psmart says the oil level might be your problem if you do the oil change I would double up on the magnets in the bottom of the box I’ve got 4 magnets in mine and they all fur up with what seams like very fine lapping past

 

[Matthew Hall]

I have spoken to a auto gearbox specialist who says they hve come across this problem before and believes it is a sticking valve that governs the changing of gears into and out of 3rd gear. They have full diagnostics and for £50 will attempt to confirm the faulty valve. They say that if the fault is material enough it will come up on the check. They are able to modify the value to fix the problem. They then re-set the ECU values which ought to cure the kick down problem.

Does this sound okay?

 

[lphot]

My box does similar over rev on 3rd, jumps out of gear on hard acceleration, or sticks in first gear has done so for 30,000k with fault, had oil changed and filter no better, specialist said no idea what the problem was but would guarantee for $5000 he would rebuild it and find the problem. Problem worse when towing, has oil cooler fitted, starts happening after hard braking or chicanes. Read somewhere it could be broken valve springs or control plate. Is this possible..