Help with gearbox oil

[sagalout]

Hi,

I've been having a few problems with my W202 C200 gearbox - it keeps going into limp home mode when I take a sharp left or stop rapidly. I found a thread with someone who had an identical problem and Ian recommended topping up the gearbox oil.

Unfortunately I dont have a Haynes manual so could someone possible be kind enough to tell me:

Where the gearbox filler is located?
How do you check the level? Is there a dipstick inside? If not can I just fill it to the top?
What type of oil do I need to fill it with?
Anything else I need to know?


Any help very gratefully recieved

 

[grober]

the gearbox filler is in the engine compartment offside rear of engine/usually with a sealed cap on top.
you need a dipstick/ level tool to measure the level which you probably dont have.
DO NOT JUST FILL IT TO THE TOP/OVERFILLING IS AS BAD AS LOW LEVEL!!!
probably best to use pukka MB transmission fluid to top up.
Fuchs is a good alternative make.
Bearing in mind your previous comments I would recommend either
a) doing a lot more research on the subject yourself first.
OR
b) entrust this to your local MB specialist who should do it for the cost of the top up oil!

 

[sagalout]

Cheers,

I presume from that then its a specific MB dipstick? I dont have any specialists nearby (at least none near enough I'd want to drive to in limp home mode!) so only alternative is local garage or Dealer (and I bet they wouldnt do it for the price of the oil lol)

 

[grober]

I take it you checked the plug as suggested previously ? If you get your car serviced at the dealer on a regular basis then they shouldnt charge you just to check the oil?

Quote:
Originally Posted by Vlad
If its a 5 speed box you may also have the infamous gearbox gremlins which tend to effect the electronic 5 speed boxes.

The problem stems from a dodgy gearbox seal which allows gearbox oil to weep out, which then travels down the wiring harness to the Gearbox ECU which it then invades and starts to cause all sorts of odd gear selection problems, loss of gears, especially top, and loss of reverse.

The only cure is a new gearbox ECU and replacement of the wiring harness and the gearbox seal.

Don't go that far just yet!

common problem is the pilot bushing 'electrical plug socket' on the Transmission 722.6 & 722.9 tend to leak and fill the plug up with oil, which causes a short in the electrical system which places the transmission into a limp home mode where it runs in 2nd gear,

simply replace the 3 o'rings and clean out the plug and all should be good.

it can also be caused by a fault in the Transmission control board which is located inside the transmission on top of the valve body, which sometimes requires replacement but the plug filling up with oil is the cause 90% of the time.

i have never seen the Transmission control unit causing a fault such as this. if you look under your car can you see oil on the transmission sump pan? otherwise unplug the connector from the transmission and you will likely see some oil come out.

 

[sagalout]

Well it went in for its service and I told them about the problem (which hasnt happenned since that one time.). They just said they couldnt reproduce it and everything seemed fine - I dont know if they checked that plug or not, and I odnt have any ramps to check it myself.

Sounds like I need to take it back to them. Just thought it was a fairly simple process which I could do myself to get it back on the road quickly. Rang my local (non MB) garage but they said they cant do it because of the dipstick, so Dealers it will have to be.

Thanks for the help though

 

[Parrot of Doom]

Don't go to the dealer. Find a local indy, plenty listed on here.

One I use is in Whitefield, J17 M60. Bit far for you though. Greenvales.

 

[sagalout]

Well its been in today to a local garage, who spoke to the MB dealers service guys when he went to get the replacement oil.

Gearbox is completely dry externally, as is the plug, however when they drained it to do an oil change they only got just over 4L out of it, and it holds 7.5 apparently so thats probably causing the problem, but my question is where did the oil go?! The garage is certain it has no leaks :/ Can gearbox oil just dissapear/burn off like engine oil? Or must there be a leak which they havent found somewhere? The car is garaged and theres never been any signs of oil on the floor, which there must be if its 3 litres worth!

I'm going to pick it up in an hour so hopefully it will drive ok.

 

[C240Sport97]

the rest of the oil is in the torque converter ...

on older transmissions, there is a drain plug on the torque converter .. you need to turn the thing until you see it.

all this from my rusty memory. no doubt someone who has actually done this can provide better information

Well its been in today to a local garage, who spoke to the MB dealers service guys when he went to get the replacement oil.

Gearbox is completely dry externally, as is the plug, however when they drained it to do an oil change they only got just over 4L out of it, and it holds 7.5 apparently so thats probably causing the problem, but my question is where did the oil go?! The garage is certain it has no leaks :/ Can gearbox oil just dissapear/burn off like engine oil? Or must there be a leak which they havent found somewhere? The car is garaged and theres never been any signs of oil on the floor, which there must be if its 3 litres worth!

I'm going to pick it up in an hour so hopefully it will drive ok.

 

[Glenn Smith]

is normal to only get 4ltrs during an oil change, depending on if the sump has been removed and if the torque converter has bee drained (if it has a plug) ihad to change my oil twice to get 6ltrs in ( no torque converter plug, but did have sump off, which holds a fair bit) if you only drain the oil from drain hole you'll get 2.5 ltrs, make sure level is correct, do not drive overfilled!!!!