Serious 7G-Tronic transmission slipping problem..
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From: Toronto
V12TT
Serious 7G-Tronic transmission slipping problem..
Transmission is slipping 1st gear (the MOST) and other gears. I searched for a while and concluded that my transmission oil probably is low and probably leaking somewhere.
So I make my way down to the dealership today to the parts department to purchase a dipstick and maybe a quart of tranny oil but I was told there's there's no dipstick made for this tranny and it's a complete sealed unit so I can't do anything about it, to check it they have to hook up some computer or something I don't know..
I was driving my car in "C" mode for a while I don't know if this has anything to do with it.
1) Does anyone else have problems with their 7G's?
2) What might be the cause for the transmission to slip?
3) Can I do anything myself without having it serviced by the stealership? My warranty just expired..
So I make my way down to the dealership today to the parts department to purchase a dipstick and maybe a quart of tranny oil but I was told there's there's no dipstick made for this tranny and it's a complete sealed unit so I can't do anything about it, to check it they have to hook up some computer or something I don't know..
I was driving my car in "C" mode for a while I don't know if this has anything to do with it.
1) Does anyone else have problems with their 7G's?
2) What might be the cause for the transmission to slip?
3) Can I do anything myself without having it serviced by the stealership? My warranty just expired..
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
No
dipstick,it gets filled through the vent tube down by the pan.Find a good indie shop to run the diagnostics on the transmission,the dealer will rip you.Or go to the dealer and ask them to check the software upgrade on the trans.There are several TSB's related to the slipping issue on the 722.9 trans so make sure they do them all.
ohlord
ohlord
Thread Starter
MBWorld Fanatic!
Joined: Jan 2007
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From: Toronto
V12TT
dipstick,it gets filled through the vent tube down by the pan.Find a good indie shop to run the diagnostics on the transmission,the dealer will rip you.Or go to the dealer and ask them to check the software upgrade on the trans.There are several TSB's related to the slipping issue on the 722.9 trans so make sure they do them all.
ohlord
ohlord
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Joined: Dec 2006
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
Yep, no dipstick on the 7G. They use a special machine that fills the fluid through the drain plug, while monitoring temperature with Star Diags. Your's should still be under warranty, so take it to the dealer and have them fix it.
Here is a PDF on the design and operation of the 7G transmission:
http://www.mercedestechstore.com/pdf...9%20062504.pdf
It is a good read to understand our transmission.
Mine had a slight leak when new and stopped leaking after a few thousand miles. I get some slipping in mine when running ethanol, but almost disappears when running premium. I have an appointment to take mine in next week.
Here is a PDF on the design and operation of the 7G transmission:
http://www.mercedestechstore.com/pdf...9%20062504.pdf
It is a good read to understand our transmission.
Mine had a slight leak when new and stopped leaking after a few thousand miles. I get some slipping in mine when running ethanol, but almost disappears when running premium. I have an appointment to take mine in next week.
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From: Toronto
V12TT
john thanks for your reply and that PDF file, my car is unfortunatly out of warranty now I exceeded 50,000miles by like 100 or something. Went to the dealership they think this is a very unsual problem and will still cover it under warranty if it's a internal problem with the transmission. I hope they give me a new transmission this one is too rough 
Super Moderator
Joined: Dec 2006
Posts: 2,403
Likes: 64
From: Camas, WA
2007 C230SS; 2014 ML350 BT
john thanks for your reply and that PDF file, my car is unfortunatly out of warranty now I exceeded 50,000miles by like 100 or something. Went to the dealership they think this is a very unsual problem and will still cover it under warranty if it's a internal problem with the transmission. I hope they give me a new transmission this one is too rough
I just hit 25K and mine will be one year old next week.If it is serious, I would imagine they would cover it, since you are barely outside of warranty. Did you get the transmission service that is required at 39K miles? Keep us informed how it goes with the dealer. Good luck.
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From: Huntington Beach, Ca.
'17 Jaguar XF
Go to the E class W211 board for 7G information. They were the field testers for MB 
Quite a few known problems that have been resolved and lots of information on applicable TSBs.
Quite a few known problems that have been resolved and lots of information on applicable TSBs.
