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Thank you for helping me. I have few more questions. If I do 3 changes by dropping the pan and refilling.
How long do you think I should run it? Do I need to drive it, or I can run it lifted? Do I need to go through the gears if I run it lifted? When should I replace the gasket and filter, after the 1st drop, or before the last one?
Also, the reason I wanted to do it, because last year I had a transmission flush done by a good trusted mechanic. He is well equipped, and used a flash machine. When I picked up my car I noticed that the filter hasn't been changed and he used BG PN312 universal Synthetic ATF. Apparently many mechanics use it for 722.9. Its application chart lists Mercedes 236.14; ATF 4134; 001989680310 and other MB. He said that the filter doesn't need to be changed at such low miles (it has under 50,000 now). After reading these forums I got nervous and decided to change the filter and fluid with Fuchs Titan 4134. I already purchased everything including filling adapter. I guess, I can bring everything to him and have him flush again using the machine with the Titan fluid and replace the filter. What do you think?
I would do two drains and refills simply through the drain plug. Then for the third, drop the pan (clean it ) and change the filter. I'd do all this lifted, but it will take some time. The level needs to be checked at 113F, but that's not operating temp (195F), but you need to get the oil up to full operating temp between each change. So, you have to let it cool some between level checks.
I thought if I drain through the drain plug without dislodging the overflow tube, only small amount would come out. But if I dislodge it, then I wont be able to bring the fluid back to the level without taking the pan down. Am I wrong?
Yes, dislodge the overflow tube to drain, then refill with as much fluid came out (usually 4 quarts). Then run it up to operating temp and through the gears. Repeat this once, then drop the pan on the third drain/refill.
Thanks again. I'm going to do that. BTW, today I called two MB dealers and gave them my vin, and ask if they can tell me by the vin # if my car has the torque converter drain plug. They both said yes, it has it. I can't believe I could miss it. I'm wondering can they be wrong??? I probably need to look again.
The torque converter drain plug is a bit of a drama. Sometime during the MY2000 build (so calendar year 1999/2000), MBZ decided to delete the torque converter drain. After all, the 722.6 transmission was sold as "sealed for life", so some lawyer or actuary likely explained how having a drain might contradict that, and it would save $2.00 per car to no have it. In 2003 (for the MY2004 R230), the 722.9 was introduced and it inherited the absence of the torque converter drain plug from the 722.6 as these were also sealed for life.
Unfortunately, it was soon discovered that the fluid pumps and torque converters in the 722.9 were deteriorating and generating excessive particulate. MBZ responded with a "suggestion" to dealers that the 722.9 might need a one-time, 40K mile fluid and filter change. Remember, German engineers don't make mistakes, they just suggest adjustments. Anyhow, after they realized that more than half the fluid was in the torque converter, the re-introduced the drain in it. This was sometime in calendar year 2004-2005. So, most pre-MY2005 cars do not have the torque converter drain, and maybe half the MY2005's. You cannot tell by VIN. You can only tell by looking.
I did go under the car again to check the drain on the TC. My car definitely doesn't have it. I also went through the 722.6 ATF flush forums, and it looks like the write up done by C230 Sport Coup, flushing through the upper transmission house disconnected from radiator is the easiest and complete flush for the cars without TC drain plug. I just would like to verify few things.
Can this exact method be used on my 722.9?
They also replace the electrical connector that often leaks. Does 722.9 have that connector?
Does it have to be done at the operating temperature, or cold engine?
What is the part # for the O-ring on the tran line?
Help and advise are appreciated.
The 722.6 and 722.9 cooling systems are identical. In fact, the transmissions themselves are not that different, so I would assume the flush would work the same way.
One big difference is the electrical connector. The TCU on the 722.6 is external, so it needs a large harness to connect it to all the internal servos and sensors, and its bushing is prone to leaks. The 722.9 uses an internal TCU, so it has only four leads coming out of it - CAN and power. That connection rarely leaks.
The o-rings on the cooling lines may be fine without replacement. If they do leak, then just get a suitable one - it does not need to be the OE part.
I'd like to report that today I did the transmission flush with filter change. Because my 722.9 doesn't have the TC drain, I flushed it through the upper radiator tran line. I used the garden sprayer to pump the ATF up. It worked great. Everything went smooth, just time consuming. Thank you all for your help.
Did you take a note of what quantity of fluid you removed and what quantity you put in.
As you will see in my post I am having problems with not getting the full amount back into the transmission.
Yes, I did. From the pan, after draining and removing it, I got 4 L. Then I pumped 4 L in. Then flushed 3 times with 2 L out and pumped 2 L in each time. In the last 4th flush I flashed 1 L out (new fluid was already coming out) and pumped 2 L in. So I got total 11 L out and put 12 L in. And then at 45C I had the fluid coming out in constant flow. I used Fuchs Titan ATF 4134.
Since you did a flush, you can't really count that as the capacity. I can tell you this - the last one I did on my SL, I drained the pan and the torque converter. I did not measure what I got out, but I assumed around 9 quarts. I pumped in 10 quarts before doing the measurement, and it overflowed (there is a an overflow valve on top of the transmission). I did not do an exact measurement, but I suspect I put about 8 quarts back in. Also, I used SDS to verify the temperature, but I also checked with my IR thermometer and they were the same.
I have 2008 ML320 CDI, with 722.9 transmission, I did fluid flush on it last Sunday, Now i am having some issues,
Here is what I have done,
Drained TC, put new filter and gasket,
I have used Fuchs Titan 4134 ATF
Filled in 9 liters of ATF initially
Started the engine and let the temp rise to 45c/113F,
opened the drain plug while engine idling, 800 ml ATF came out.
then it was a light drip, so I closed the drain plug.
turn off engine.
Next day I noticed that fuel economy decreased, and it takes higher RPM from engine to accelerate.
there is a minor noise coming from TC, as if it is running low on ATF.
Now I am concerned that if fluid level is correct and
ATF spec is right?
04-24-2017, 09:17 PM
