Torque Converter Drain During Transmission oil change ?

[mrix]

Hello all, I am planning a Transmission filter and oil change on my Mercedes W204 C350 2013, while looking at some videos I noticed some people also drain the torque convertor ? how important is this ? and why, I say why because the oil seems to be supplied by the same oil from the transmission sump ?
Thanks for any thoughts and feedback.

 

[Blobcat]

The torque converter holds ~half of the ATF so it really should be changed as well to give a full change. It doesn't drain out when you take the transmission sump off.
Quite a few threads on it here, please have a search

 

[mrix]

Hello and thanks, obviously if it does not drain out it will contaminate the New oil when added so it does seem very important to drain it.

 

[EmilysDad]

But bear in mind that not every torque converter actually has a drain plug so changing around half the fluid is the best you'll get.

 

[Chrishazle]

With a 204 it should be relativly easy to do box and TC together - had mine done a couple of years ago. However, bear in mind refilling is not simply add the required amount of oil, it has to be brought up to temperature to get the level right, and I believe too much can cause electroplate problems, so check that whoever you get to do the job knows the required procedure and has the relevant equipment! Add your approx location to your profile, there may be a known good indie close to you that someone on here can recommend.

 

[Tony Dyson]

Changing at the manufacturers' intervals I would drain the TC and also flush through the heat exchanger which contains around a litre of oil which doesn't drain out of the sump either, partial changes are a personal choice option.

 

[mrix]

Hello it is a job I will be attempting myself, I have seen so many different YouTube videos it is a very doable job for the DIYer
I have already hunted down the parts and have looked very closely at the procedures, Its actually been a lot of fun replacing parts myself, almost become a hobby ha ha, thanks for the feedback much appreciated.

 

[V6Matty]

Just noticed this is the 350 engine so it will be a 7g box, meaning it’s a full from the bottom only job,

 

[Tony Dyson]

But bear in mind that not every torque converter actually has a drain plug so changing around half the fluid is the best you'll get.

Unless you flush it, as in this video...

On a related note, do any owners of a manually operated Pela/Sealey/Other Vacuum oil extractor pump know if any of their models have the facility or can be configured to pump FROM the reservoir and not into it?

 

[EmilysDad]

On a related note, do any owners of a manually operated Pela/Sealey/Other Vacuum oil extractor pump know if any of their models have the facility or can be configured to pump FROM the reservoir and not into it?

I'd very much doubt it but I know of others that have used garden sprayers to pump ATF into a gearbox.

 

[Tony Dyson]

I'd very much doubt it but I know of others that have used garden sprayers to pump ATF into a gearbox.

Yes I can see that, I plan on using my MM Electric pump when the time comes around again, if I'm still alive that is with the current mileage I'm doing lately!

 

[robin.large]

The Torque Converter doesn't drain through the sump.
It holds half the ATF.
So you have 2 choices. You can leave it be and accept you will improve the oil in there, or you can drain everything.
You do that by loosening the oil cooler return line at the gearbox until all done.
You can't use a pump to extract the oil.
You need to be careful filling as you will have to fill in stages.
Fill. Fit drain plug, run engine. Repeat.
You need a pressurised bottle to fill through the drain though.
It's messy.....

Sent from my KB2000 using Tapatalk

 

[Wighty]

Pardon our interruption...

I use these with a plumbing isolation adapter and the gearbox sump adapter

 

[Jim2]

I have the professional model pump, but I have a jury-rigged one as well. I used an clean (very) empty 5 ltr oil container. I inserted a valve from a tube, and a section of the right sized plastic piping with a piece of copper pipe inserted in the cap of the container feeding the trans pipe. A foot pump pressurised the container, and BINGO...problem solved.