Auto box jamming in 3rd gear

[richarp]

I have an S500 (2002) W220 with 120,000 miles under its belt.
The car has started hunting through the auto box and jamming in 3rd gear whatever speed it is doing.
I have been told recently that Mercedes have realised a problem where the radiator has corroded and allows the coolant and ATF to mix, this in turn eventually failing the gearbox. The story I have been told is Mercedes are trying to keep this quiet as the replacement cost of a autobox is in the region of 6 - 8 thousand pounds.
Has anyone else heard of this problem and that Mercedes are keeping Quite OR has anyone got a fix for this. [THE CAR IS KEPT SERVICED AND THE ATF LEVEL HAS BEEN CHECKED].

Regards Pat

 

[television]

Hello and welcome,, first the valeo rad fault does not apply the the 220,, though it could be possible on any rad.

Secondly the antifreeze getting in the gearbox does not cause the box to jam in one gear,,it is more than likely the conductor plate circa £150 that has gone if there are no other symptoms displayed like ABS BAS on the dash.

One does a glycol test to check but as I have said it would not give you that fault

 

[rpe2]

Seconded. My W210 is doing the same at the moment and the fault code says 'Speed Sensor', which means as Malcolm suggests.

Will do mine when I have a spare 10 mins (probably 2015)

Richard

 

[richarp]

Thanks for the replies lads, I will mention it to the garage (Merc-care)

 

[colechelle]

Seconded. My W210 is doing the same at the moment and the fault code says 'Speed Sensor', which means as Malcolm suggests.

Will do mine when I have a spare 10 mins (probably 2015)

Richard

is that a wheel speed sensor or a internal gearbox speed sensor, that the more common one on the 210???? not a 10 min job!!!!!!

 

[rpe2]

A gearbox sensor.

I know it's quite involved, ho hum...

Richard