I'm finding it difficult finding a shop to service trans as per manufacture procedure. dealer and other shops do not drain torque converter, but charge same as if they had.

 

Do it yourself? It isn't hard.
Drain and fill every 30-40K miles and the fluid never really has a chance to get that dirty in the first place. Works well on my Duramax too; drain what's in the pan and spin on a new cartridge filter. Got 315K miles on it without issue. The Benz is a little more involved since you have to actually take the pan off, but not a big deal.

 

I think it's because the torque converter drain plug is not aligned with the access hole.
The dealer or repair shop sees the problem in getting to the drain plug and doesn't do any further digging, just eliminates the step. MB released a bulletin saying there is a side access hole and fluid will drain from the normal drain hole, which I take as to being the access hole at the bottom of the bell housing. But if the drain plug isn't positioned at the bottom - you won't fully drain the TC. I would interpret the steps as being turn over engine to align TC drain plug with the side access hole, remove drain plug, turn engine over until it drains at 6 o'clock, then turn engine again to align with side access hole and re-install drain plug. Or, you do the mod as in the video. I did the mod and it is remarkably easy and will make future changes much easier.

 

Not all torque converters have drain plugs, this is widely posted on this site. There has been no model designation or production year identified to determine if a torque converter has a drain plug or not.

Drain, new filter and refill without torque converter drain is better than no service at all. MB transmissions are dependent on having the oil changed, so be sure to do it.

 

Ah, but they do have a tool to do it without drain plug in converter. They just want more money for installing one bolt and shop air. I may just invest and do service myself for a fraction of the cost at the cheapest shop estimate.

 

Please describe draining the torque converter when it has no drain plug. WIS is best if you can post this indicating the factory service procedure.

 

Sure, a tool that bolts to where filter plugs in, regulated air pushes fluid out converter and possibly the oil cooler. Here's a link to FCPeuro, they have the tool kit, covers other vehicles too, but individual tool can be found elsewhere. There is a video on FCPeuro that describes operation of tool. The video shows 722.6 but also works for 722.9 as well.

https://www.fcpeuro.com/products/tra...h-kit-cta-7650

I'll save about $300 then subtract for the cost of tool, so it pays for itself the first service. Hope this helps

 

Interesting.

Is the tool guaranteed not to blow out o-rings, seals and gaskets?

I wouldn't use this tool or a non-WIS transmission service procedure like this one, but to each their own.

 

You have to set the regulator to recommended pressure, not full pressure. That's why it takes a bit to flush it all out.

 

The 5 G transmissions on W210 did not have TC drain plugs, but as I know all 7G and 7G+ transmissions do have them.
Dealers don't drain TC period and I doubt any of them will let the transmission drip for some time.
I found that letting pan down overnight will drip another liter +, what is another 15% of capacity.
So at final point, when I can get almost 5 l of old fluid to drip, draining TC is not a big priority and I decided to end on this point.
The 7G transmissions do have electric fluid pump at the bottom, therefore the access is at the angle. Draining TC at this point comes with big mess, when you will never get 100% of the fluid anyway.
I did it before and was not happy with the mess.

 

A Start-Stop 2014 is so easy to drain the TC and remove the AUX tranny oil pump. No fluid mess.
Fluid in TC alone is A LOT, not 1 liter, it is more like 2ish liters if I recall correctly.


Drain first from oil pan. I leave it like 2+ hours or so.


After 2+ hours the2 oil holes to/for AUX tranny oil pump has very little oil trace left.




I got enough working height using Quick Jack, like 50cm.


I use my boroscope camera to find the TC drain plug while spinning crankshaft, me alone so no choice. Any small action camera with wifi feature or a 2nd cell phone or tablet you can use too to spot the TC drain plug
if you are all alone.









Make sure you buy a new drain plug as it has special sealant.

 

So you are accessing TC plug via hole from removed pump?
Good to know the option.
Are you getting new gasket for the pump?

 

Actually, my '12 has a converter drain plug, my '13 does not, go figure...

 

just overfill it and let it drain, not a huge deal. Nobody really does the TC drain, not even the dealer, not even when you show them the TSB that says to do it that way

there is a signifigant amount leftover though, 2L get left in there. just run extra fluid through the system a little at a time until it drains clean enough for your liking. This is cheaper and more time efficient than buying a completely different transmission service kit and doing it again in 30k when the fluid degrades and you get that iconic 722.9 shimmy. the effects of fresh fluid also wear off on the half-change after a couple months which is sad

 

There is no gasket like a tranny oil pan. 2 unique shaped seals which are re-useable . I would replace it by next tranny oil change though, because it would be 11 years old.

================


Chris wrote : Nobody really does the TC drain, not even the dealer, not even when you show them the TSB that says to do it that way


Chris,
My Indie is the one who taught me how to do a proper oil drain and he always drain the TC when doing cars with TC drain.
I guess your area has 90% lazy techs ....LOL




Tranny oil aging and effecting its smoothness or modulation response ( let alone rough gear change ) is when one is not sensitive enough to feel change or believed too much in MB 75,000KM or 5* years recommendation ( *MB In my country )
Even a mere 11,000KM/ 6,000 miles tranny oil but at 4 years old is already effecting tranny modulation a tiny bit. That is what I experienced in 2018 when I first got the car.

I do 2 years tranny oil change, even if my car does only say 5,000KM. 2 years for me is never above 15,000KM for sure, for nowadays.




If in E mode, this 7G+ tranny is the best bumper-to-bumper traffic jam superb slow-mo crawler I ever owned. In E, it is then 2nd gear as lowest gear.
No other Japanese cars I own, their tranny can match this 7G+ for the low crawling speed smoothness and throttle modulation response for traffic jam, I guess because they are 2 liter at best and 1st gear is always chosen.
I don't know how MB does it but its throttle program and the tranny program is really really good for BAD traffic jam, so civilized, so elegant.
The brake modulation itself has different program for super slow traffic jam and I love it.
It is funny, when people tend to praise fast tranny response, but my favourite is the bad traffic jam scenario....hahaahah. Well, 70% of its normal life would be in BAD traffic jam.
For aggressive driving, 7G+ in Sport mode is not bad, not the fastest but very smooth and decently sensitive if your oil is always fresh.

By 60MPH or 100KM/H in E mode, it will hit 7th gear already, tranny is forever looking to get engine to be under 1,500 RPM.
If tranny oil is fresh, by throttle modulation one can choose ( by practice ) with ease to drop to 6th or 5th or 4th gear.

When I got it first time in May 2018, before tranny oil change, such throttle-to-tranny-gear-change modulation precision is not possible with ease and speed.
So I thought damn, typical DUMB tranny like in older cars of 4 speed AT. When with new tranny oil I was surprised most by the now much improved throttle-to-tranny-gear-change modulation precision
Kicked down response is also faster with new tranny oil, but kick down is not the true measure as it will always happen when we depressed the last final click on the throttle/accelerator pedal.

 

7G+ in my diesels always start on 1st gear and I prize it for smooth changes. When towing, (with my GLE) quite often it will drop 3 gears on the hill and I barely notice.

 

Seems mine, a 2014, Stop-n-Go model, does not have the Torque converter drain plug. So the flush tool is a must, or a second fluid change is in order. Orrrr, just drive for another 30k and repeat.

 

Surya

I would like to flush the trans cooler and lines when I do my fluid change in a couple of months. Where is the best location? I have seen illustrations showing a banjo bolt at the bellhousing. Is that the return line? 2016 E350 RWD with stop and go

Ron

 

And then I find this, seems like a far better method, with video instructions, better than just pictures, LOL.

 

I never flush my cooler lines and the cooler itself, it is not that much oil capacity by looking at its size.
Most important for me is that I can get the torque converter content flushed out, which I just look at my maintenance log, it is worth 3.5 liters. 1 US gallon is 3.78 liters.
Also oil cooler has thermostat, I do not know where that is located, at tranny or at cooler ?