how hard is it to replace the shift solenoid seals and clean shift plate?
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Joined: May 2009
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2011 c300 4matic
how hard is it to replace the shift solenoid seals and clean shift plate?
just wanted to see what problems i can potentially run into while doing that
2011 c300 4matic updated transmission
2011 c300 4matic updated transmission
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Joined: May 2024
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From: Northern Indiana
2014 c300 w204.080 3.5 v6
I dunno I've never done that job but inside the trans is always somewhat challenging but doable.
You can look on this website and see if you can find your answer.
https://charm.li/Mercedes%20Benz/
You can look on this website and see if you can find your answer.
https://charm.li/Mercedes%20Benz/
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
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From: Northern Indiana
2014 c300 w204.080 3.5 v6
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Member
Joined: May 2009
Posts: 209
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2011 c300 4matic
previous idiot owner put old fulud into this. and probably bunch of other additives.
car would shake when it was in gear in every gear
i replaced fluid then shaking slowly went away.
but as shaking went away the second gear shift delay became more and more pronounced. sometimes it happens in first and second gear also. very rarely the car would jut not go in gear until i let go the gas pedal only in low gears though
never happened when i smash off the light hard. only low throttle low gear.
i havent done second transmission flush yet.
but i did reset the tcm and everything else multiple times... nothing changed.
car would shake when it was in gear in every gear
i replaced fluid then shaking slowly went away.
but as shaking went away the second gear shift delay became more and more pronounced. sometimes it happens in first and second gear also. very rarely the car would jut not go in gear until i let go the gas pedal only in low gears though
never happened when i smash off the light hard. only low throttle low gear.
i havent done second transmission flush yet.
but i did reset the tcm and everything else multiple times... nothing changed.
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Joined: Jul 2023
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S550 V8, CL600 V12, SLK32 AMG
if you have the 5 speed, its fairly easy but messy.
- Drain transmission fluid
- Take off pan
- Take off valve body. Be careful. Take out electrical plug first
- Do whatever you want to do with valves
- Install new conductor plate and plug holder. The transmission will leak into the plug and up the wires.
- Put everything back together
The other transmissions should be similar, but you cannot just get a new conductor plate, it has to be programmed to the car.
- Drain transmission fluid
- Take off pan
- Take off valve body. Be careful. Take out electrical plug first
- Do whatever you want to do with valves
- Install new conductor plate and plug holder. The transmission will leak into the plug and up the wires.
- Put everything back together
The other transmissions should be similar, but you cannot just get a new conductor plate, it has to be programmed to the car.
Last edited by waterzap99; Apr 21, 2025 at 12:38 PM.
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From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
He has the 7G tranny. He cannot purchase a new conductor plate from the dealer for self-install; the dealer will only sell it if they do the install.
We don't know what this problem is. It could be the conductor plate, or solenoids, or clogged fluid channels.
We don't know what this problem is. It could be the conductor plate, or solenoids, or clogged fluid channels.
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
previous idiot owner put old fulud into this. and probably bunch of other additives.
car would shake when it was in gear in every gear
i replaced fluid then shaking slowly went away.
but as shaking went away the second gear shift delay became more and more pronounced. sometimes it happens in first and second gear also. very rarely the car would jut not go in gear until i let go the gas pedal only in low gears though
never happened when i smash off the light hard. only low throttle low gear.
i havent done second transmission flush yet.
but i did reset the tcm and everything else multiple times... nothing changed.
car would shake when it was in gear in every gear
i replaced fluid then shaking slowly went away.
but as shaking went away the second gear shift delay became more and more pronounced. sometimes it happens in first and second gear also. very rarely the car would jut not go in gear until i let go the gas pedal only in low gears though
never happened when i smash off the light hard. only low throttle low gear.
i havent done second transmission flush yet.
but i did reset the tcm and everything else multiple times... nothing changed.
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From: Bloomington, IN
2010 GLK350, 2021 Taco, 2019 Lexus GX460, 2009 BMW 335d, BMW 328xi
Same thing but different
I just went through pulling the valve body off my GLK (w204), so same thing. Relatively easy, but messy. The oil pan removal is pretty straightforward, 6 bolts. The valve body is 10 bolts and the electrical fitting. Once the valve body is out, the solenoids are held in place in pairs, with a single bolt and spring-clamp. The solenoids can be safely cleaned in an ultrasonic cleaner. With the solenoids out, you can coax most of fluid out of the valve body by flipping it end over end, side over side, corner over corner, until nothing else comes out. I recommend testing all solenoids by resistance, and for action with a 12v power supply. I also recommend replacing the solenoid o-rings while you’re in there.
valve body and transmission pan bolts are aluminum one-time use bolts
valve body and transmission pan bolts are aluminum one-time use bolts
