SL55/63/65/R230 AMG: Oil found on TCU module- HELP
Thread Starter
Member
Joined: Jan 2019
Posts: 164
Likes: 13
From: NJ
2003 SL55 AMG GT , 2000 BMW 323I coupe
Oil found on TCU module- HELP
I'm in need of some help to pinpoint a problem.
I was changing my TCU module on my 03 SL55 AMG and noticed some oily substance on the module and on some of the module pins.
I've never experienced any codes or shifting issues, yet, but would like to know where that oil could be coming from. Does anyone know if there are any oil lines, tees or fittings in the TCU mounting location that can be causing this oil to be getting in that area? Location is passenger footwell area behind the carpeting on far right-side under glovebox.
Thank you in advance for ideas.
I was changing my TCU module on my 03 SL55 AMG and noticed some oily substance on the module and on some of the module pins.
I've never experienced any codes or shifting issues, yet, but would like to know where that oil could be coming from. Does anyone know if there are any oil lines, tees or fittings in the TCU mounting location that can be causing this oil to be getting in that area? Location is passenger footwell area behind the carpeting on far right-side under glovebox.
Thank you in advance for ideas.
MBWorld Fanatic!
Joined: May 2009
Posts: 1,187
Likes: 239
From: Santa Clara, Ca
2003 SL55 / 2002 SLK32
As was indicated, you need to replace the transmission connector seal (also called "pilot bushing" by mercedes, why, who know) . The fluid "wicks" through the harness (to the TCU) when this seal assembly fails.
https://www.mbdirectparts.com/oem-pa...ing-2035400253
This part is less than $15 and should be replaced when you service the transmission (or every 50k miles).
It is easy enough to change (you will lose very little fluid when you take it out). Do make sure that you do NOT do it when the the car is warm (as you run the risk of spinning the captive nut that it is secured to).
As an added precaution on my 2003 sl55, I modified the mounting bracket for the TCU so that the connector is at the bottom (making it so if fluid ever reached the TCU, it would drain out around the connector rather than make its way onto the PCB)
HTH,
Chris
https://www.mbdirectparts.com/oem-pa...ing-2035400253
This part is less than $15 and should be replaced when you service the transmission (or every 50k miles).
It is easy enough to change (you will lose very little fluid when you take it out). Do make sure that you do NOT do it when the the car is warm (as you run the risk of spinning the captive nut that it is secured to).
As an added precaution on my 2003 sl55, I modified the mounting bracket for the TCU so that the connector is at the bottom (making it so if fluid ever reached the TCU, it would drain out around the connector rather than make its way onto the PCB)
HTH,
Chris
