Changing MB GLE transmission fluid

[MaximaGuy]

I have 40K on my GLE and want to do a return line flush without dropping the pan.
Understand the rubber lines coming to radiator are nicely done and crimped nicely.
Anyone done the return line flush by disconnecting one of the radiator lines and running dry the transmission to get old fluid out and refill via the return line by pumping new fluid back into the pan.

I don't like pan drops, anyone have suggestions.

 

[slacktide_bitog]

Do you have the 9-speed or 7-speed? Don't they have drain plugs?

 

[The Critic]

Pan needs to be dropped; it's the most important part of the service. MB wants the filter replaced. Yours is the 722.9, right?

 

[MaximaGuy]

Mine is a 7 speed transmission. Its 6 yrs old but not much miles on it and during my service visit to dealership it was recommended to be replaced

 

[Astro14]

I would drop the pan, change the filter, then, with fresh fluid in the pan, run the cooler line exchange that you’re proposing.

I’ve not done this car/trans combo, but BenzWorld has some very active forums for your car, and I bet one of them has done this. Start your search here: https://mbworld.org/forums/gle-class-w166-206/

I had to buy a couple of fittings to connect with the cooler line on mine (M14, I believe) to do the cooler line flush. I also needed to buy the “service tool” that is a calibrated dipstick. Easy to check/set level if the transmission is at the proper temperature, and a good scanner is required for that.

On my two cars, a cooler line flush is actually MB procedure, and there is WIS information on it.

It’s a matter of getting someone with WIS to publish that procedure and then getting the fittings to set it up. You’ll need about 14-16 liters of fluid.

FCP Euro has the parts and fluid for a reasonable price, though they imply a pan drop/refill, not a flush, in their write up.

https://www.fcpeuro.com/products/mercedes-722-9-transmission-service-kit-liqui-moly-7229late

 

[Astro14]

I have 40K on my GLE and want to do a return line flush without dropping the pan.
Understand the rubber lines coming to radiator are nicely done and crimped nicely.
Anyone done the return line flush by disconnecting one of the radiator lines and running dry the transmission to get old fluid out and refill via the return line by pumping new fluid back into the pan.

I don't like pan drops, anyone have suggestions.

One other suggestion - PM me your VIN. When I am down at my shop tomorrow, I will plug it into my WIS. I may be able to pull up the official MB procedure for your car on my WIS, but my WIS is an older installation, so, I would have to plug in the VIN to check. If it’s on my machine, I can post the MB information back here.

 

[The Critic]

Mine is a 7 speed transmission. Its 6 yrs old but not much miles on it and during my service visit to dealership it was recommended to be replaced

Needs filter replacement. I have a thread on here on how the job is done.

 

[JTK]

Does this 7spd have the plastic pan with a single port in it? Once the plug is removed, you index/clock a specialized fitting placed into the port from the MB tool kit to put it into drain, fill or level check mode. I believe most of the tool kits specific to the pan also come with the refill fitting with a hose barb on it.

My 2022 Nissan Frontier has the Jatco copy of the MB 9G-Tronic with this setup. There's a Frontier owner or two who have done just spill and fills with them and plan to do pan changes after 60K miles. These are weird pans with two different filters bonded into them, lots of magnets and a fluid equalizer / riser tube.

 

[MaximaGuy]

The plastic straw is a push-in levelling setup - a drain and fill nightmare. If the leveler is dislodged one has to drop the pan - my Lexus has a screw in leveller!!

Very interesting DIY setup and that is why I want to do a return line change and doing everything by measuring what comes out and what's pumped back in.

 

[The Critic]

The plastic straw is a push-in levelling setup - a drain and fill nightmare. If the leveler is dislodged one has to drop the pan - my Lexus has a screw in leveller!!

Very interesting DIY setup and that is why I want to do a return line change and doing everything by measuring what comes out and what's pumped back in.

It is the exact same setup as your ES350.

Filter change every 40-60K is important for these units. Pan bolts are also one-time use.

 

[Astro14]

Here’s what I found, and I believe it’s accurate…though my WIS is older. Down in my shop, I only have a printer. And the WIS computer is not connected to the Internet. I can export these things as a PDF, but since it’s not connected, and BITOG doesn’t allow PDF uploads, I’ve taken pictures after printing.

First is the “oil and filter change”

 

[The Critic]

My DIY guide:
https://bobistheoilguy.com/forums/threads/mercedes-722-9-transmission-service-tips.280379/

Disclaimer: every 722.9 application is a little bit different; capacity and level check instructions can vary. Some models have the torque converter drain plug, others do not. Always consult the service procedure that is specific to your VIN.

 

[Astro14]

The subordinate task of “remove automatic transmission pan and filters“ is shown in these two photos.

 

[Astro14]

The task of “fill automatic transmission with fluid” is illustrative. Here are the photos:

 

[MaximaGuy]

Folks I need an educated answer to the process I intend to do to flush tranny and don't want to drop the pan for a myriad of personal reasons (opened a few tranny filters at 200K and they have been rather a screen). I have always trusted flushes and that keeps everything clean inside the pan for the most part. Unlock the C clamp on the radiator end of the line coming out of the tranny and start car and run it dry. Then fill the pan with the hardware 6L and then run it dry - that would have gotten all of the old fluid out. Refill what was removed and check level and call it a day... I have done this in all my cars with no problems whatsoever. Any concerns with this process..

 

[The Critic]

Folks I need an educated answer to the process I intend to do to flush tranny and don't want to drop the pan for a myriad of personal reasons (opened a few tranny filters at 200K and they have been rather a screen). I have always trusted flushes and that keeps everything clean inside the pan for the most part. Unlock the C clamp on the radiator end of the line coming out of the tranny and start car and run it dry. Then fill the pan with the hardware 6L and then run it dry - that would have gotten all of the old fluid out. Refill what was removed and check level and call it a day... I have done this in all my cars with no problems whatsoever. Any concerns with this process..

Follow the manufacturer’s instructions and discard your personal experience - it doesn’t apply here. MB requires the filter change for a reason (all of their automatics have required it for decades), so stop trying to outsmart them.