DIY 722.9 7G-tronic 7-speed automatic transmission service thread
Member
Joined: Apr 2013
Posts: 129
Likes: 3
From: Fort Hood, TX
C300 W204 Luxury
I have a 2012 c350, the TC bolt was a pain to reach....a tiny allen key was what did the job. With that being said, I don't think 4 litres came out of my TC. Maybe 2 at the most, and the fluid was green and very clean. The dealership I bought it from must've serviced the transmission fluid but i haven't seen green atf before.
FCP euro only supplies 7 litres of ATF in their kit...at the drain portion at the end of the maintenance...the ATF was trickling out of the drain hole, so i figure it's atleast at the minimum amount required. Where would the other 2 litres be?
FCP euro only supplies 7 litres of ATF in their kit...at the drain portion at the end of the maintenance...the ATF was trickling out of the drain hole, so i figure it's atleast at the minimum amount required. Where would the other 2 litres be?
Junior Member
Joined: Sep 2018
Posts: 17
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c300 sport
Can't always get to the TC drain plug....
Hi all- So dd my 70k trans service on my 2014 c300 4matic sport last night. Brand new Fuchs titan 7134 blue fluid and the like. However, when I went looking for the rubber plug at the mouth of bell housing, there wasn't anything to be found of the sort. What I did find there was a secondary transmission fuild pump part no. 221 270 0197. I found this baffling as there had been no mention of this in all the vids I found and writeups I found for the 722.9 service. Going off a hunch, I pulled this pump off. The pump was indeed covering a rubber plug that revealed the tc. after what felt like and hour of cranking the engine by myself i found the tc plug. Then the real problem reared its ugly head: the plug was canted on an angle such that the face of the plug and my access to the torx head was aimed inward from the opening and there was no way to get a bit in there. Short of filing away material in the witness hole to get to it, I was out of options and, alas, I completed the service without draining the tc.
Wish I had pics but I didn't stop to snap any.
Anyone run into this scenario on their 2014? It was completely different from all of my research.
Wish I had pics but I didn't stop to snap any.
Anyone run into this scenario on their 2014? It was completely different from all of my research.
MBworld Guru
Joined: Dec 2009
Posts: 10,782
Likes: 1,011
NO LONGER ACTIVE
At least you could have filed out the access hold to get to the TC drain. On the W164, they put the access hole on the wrong side of the TC so you cannot access the drain at all. I would drive a few hundred miles, drain and refill the pan, then do it once more and you'll get over 90% of a fluid change.
Newbie
Joined: Nov 2019
Posts: 7
Likes: 0
C250 Sport
Rubber plug lost inside TC housing
So today, just when i was done changing the tranny fluid on my wifes c250 all i had to do was put the torque converter rubber seal back. Before i could claim 100% completion and victory, i pushed the rubber seal a little too hard with my finger and the whole thing went into the housing. I used my finger and any other thin, long object to try to fish that rubber seal out. I was almost successful a few times and even "lost" it a few times (the rubber seal not me although i felt like it at times) before i was able to coax it closer to the TC opening again but just couldn't find my needle nose pliers to pull it out (where is it when you really need it?). I even had my wife start the engine while i was underneath trying to see if the TC bell housing might shift the rubber seal from the TC rotation. I did see it whizz by but just cannot find it anymore.
My concern as you may already know is if any real damage can result??? I'm hoping the rubber seal shouldn't interfere with the shaft or any other critical portions of the transmission. Technically, the rubber seal is still outside of the TC bell isnt it? Probably not enough assurance but i did drive the car around a half mile or so to check if there was any noise. Need your guys' experience and knowledge on this! Thanks!
My concern as you may already know is if any real damage can result??? I'm hoping the rubber seal shouldn't interfere with the shaft or any other critical portions of the transmission. Technically, the rubber seal is still outside of the TC bell isnt it? Probably not enough assurance but i did drive the car around a half mile or so to check if there was any noise. Need your guys' experience and knowledge on this! Thanks!
Last edited by Stevie818; Nov 3, 2019 at 06:17 AM.
Joined: Nov 2016
Posts: 7,847
Likes: 3,496
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
and this short-arm hex wrench:
btw, the WIS does instruct to remove the external transmission oil pump in the procedures.
Last edited by JettaRed; Nov 5, 2019 at 07:57 AM.
Newbie
Joined: Nov 2019
Posts: 7
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C250 Sport
Newbie
Joined: Oct 2021
Posts: 4
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From: Hastings, NE.
2012 C300 sport, 89 Chevy Suburban, 2019 389 Peterbilt.
I've had the trans flushed on other cars and trucks I've owned. After the flush I went home and dropped the pan and put in a new filter and cleaned the pan. Thats the way to do a flush.
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Junior Member
Joined: Jun 2022
Posts: 17
Likes: 1
W204 C300
Joined: Nov 2016
Posts: 7,847
Likes: 3,496
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Parts should be under $300 and no more than a couple hours of labor. $600 seems closer to what it should cost.
MBWorld Fanatic!
Joined: Nov 2003
Posts: 2,412
Likes: 497
From: Earth
2015 C300 4Matic Sport
Last edited by benzdude; Jul 27, 2022 at 06:39 PM.
Junior Member
Joined: Jun 2022
Posts: 17
Likes: 1
W204 C300
You can get a quality Liqui Moly kit with a Mann filter for $169 on sale sometimes, and its enough for the converter drain as well.
MBWorld Fanatic!
Joined: Nov 2003
Posts: 2,412
Likes: 497
From: Earth
2015 C300 4Matic Sport
So I went back today to get my car and my regular service guy was there. He tells me the Transmission flush is only $580 total, so not sure what the other guy was quoting. Jeez, good thing i opted out.
Newbie
Joined: Dec 2019
Posts: 10
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2014 MB C250
I use an IR gun to see temp of fluid as it overflows from tranny drain after letting car idle in park about 10-20 minutes depending on outside temp . I use Pentosin 134FE on my 2014 C250 with the 722.9 tronic transmission since it meets the MB spec and think Penstosin make the MB Blue tranny fluid anyway .
