GSRX,

Someone in Denmark(somewhere out there) did it. It is not hard to do. The 722.6 has pressure regulator solenoid that oscillates at around 1000 to 2000 Hertz and the solenoids have to be fired in sequence, and fired in sequence in down shifting.

The hardest thing is to get the auto up shift and auto down shift.

A poor mans manual shifter would be easy to create for the 722.6-like a paddle shifter using a Arduino and some transistors.

The person in Denmark did it with a Arduino Embedded development board-these are $40-the high school systems of the US are teaching kids to program on Arduinos.

The 722.6 is the best transmission for anything and everything-Power capacity-very easy to DIY repair-longevity is 20 to 30% more then other Mercedes transmissions-It tolerates lots of abuse-Mercedes newer V12 cars still come with the 722.6.

The great thing is the third party transmission parts makers make all the soft and valve body parts. Valve body parts on the other Mercedes transmissions are non existant, so one is forced to buy the whole valve body at a one to two thousand(at that price it throws the idea of DIY out the window). Oh, Chrysler use it too-Crossfire-Jeep Commander-I think the Charger...

Here are some good links:

Transmission

www.MSgpio.com • View topic - Mercedes-Benz 722.6 (NAG1) Automatic Transmission

mercedes transmissions

Everything you ever wanted to know about a NAG1 valve body - Cherokee SRT8 Forum

Martin

I thing that you are under estimating the simplicity of this by a lot. If you just want to shift the transmission at full pressure in sequence you could do this quite simply. You could also use a simple load to pressure control. To make the pressures somewhat linear to load. But there is a lot more going on and making it reliable and smooth is a whole other ball game. You 1st have to downshift to 1st upon startup since the transmission starts in 2nd. Then you have to have a rather complex shift pressure sequence. You run two pressure control solenoids during a shift and the pressures change from a shift sequence back to a non shift pressure table. This all has to be timed with the shift solenoid coming on. Now do you want the tcu to know what gear it is in?
THis gets really hard. There are two internal speed sensors. Both are planetary speed sensors. So instead of an input and output speed sensor which would be an easy gear calculation or an input and add a driveshaft speed sensor for the same you have to add a driveshaft speed sensor and then switch between the speed sensors from gear to gear. This is just so the tcu knows what gear it is currently in. Otherwise if you command a shift and it does not complete then it will not know any better and when you command the next shift it will not be correct any more.
Now there are people out there and some are customers of mine that do not car at all about shift quality or auto shifting or anything of the sort. But that is a rare bread.
I have thousands of hours in tuning and testing and tuning and testing to get this where it is now.

Some American electronic shift transmissions are just slightly modified hydraulic shift units, these can be operated by generating synthetic throttle pressure ( engine load ) , . governor pressure ( road speed ) then letting the rest of the valve body take it from there.

Some have a solenoid to control line pressure and cycle solenoids to command shifts. In these two cases a simple control circuit is enough.

Chrysler in the late 80's was a pioneer in the active electronic shift trans ( the 4 speed front drive 604 ) These trans need a learning sequence to operate properly. They also monitor "fill volumes" to assure proper shift timing as the clutches wear, gain clearance and take longer to apply.

Update.
Newest firmware is pretty solid. The only way to get out of sync is to be to aggressive with the shift timers. Which is just not necessary. At .4 seconds it is rock solid. If you are in manual mode you can run faster. I am running at .2 safely in one car and .3 in the other. I think that .4 will give that extra margin. It also depends on transmission setup and tune of course.
The only thing that is not working right now is simple manual mode which is not very useful to be honest. It really just works like the manual selection in the shifter. I just use full manual mode on my cars if I want to select gears. Really the only thing you would use it for is engine braking.

Just found this thread, so am putting an oar in here so I don't lose it.

I've collected:

--a running '87 300TD (124.193),
--another which has had the head removed but seems otherwise intact;
--a '94 E320 gasser wagon with bad front suspension;
--an OM606.962 block and head;
--an OM606.912 with IP and all the other parts which hang off the engine;
--and a 722.6 transmission.

Am accumulating heavy-duty swaybars et cetera. Also will soon own a spare OM603 engine and a 350SDL IP.

Exquisite mischief lies somewhere herein, I am confident.

Now I just have an urgent need to find a shop bay in the Seattle area I can rent for 3-4 months. Also I think I am going to need to acquire (or at least rent) a light pickup truck.

@whipplem104, is it in the nature of your business to take a 722.6 and build it up with kevlar clutch facings et cetera, preparatory to installing your tcu?

Please excuse my noviceness if I am barking up any wrong trees here...

I do not normally build transmissions for customers for the tcu. You are local to me though and I can discuss this. I rebuild transmissions all the time and can do this for you if you are interested. I will pm you with contact info.

Would like to put a 722.6 in my 190e. Just installed a m103 3.0 with wiseco dished pistons and t3/t4 and additional injectors for under boost. But I really would love this trans! What all would it take to make this work? I'm not far away from you whipplem104. How much would something like this run me?

It depends on what you want out of it. I will pm you and we can talk about the details.

Huge push on the tuning in for this yesterday. I finally managed to dial in the 3-4 shift.
It is a clutch to clutch shift which means that it has to be timed properly or you can get bind or a flare up like from being essentially in neutral for a short time.
I was working on some valve body modifications and realized something in my tune that would help a great deal. The problem has always been that as you try and tune out the flare up that the transmission would bounce back into 3rd uncontrolled. Pressures in the valve body and valves not in the correct position. I realized why that happens on Friday and was able to make a fairly simple change in the tuning to use as a test and completely eliminated this problem.
Then to the flare up. I have a local customer with a '73 CUDA/Challenger with 5.7hemi and a nag1 or 722.6. Completely stock transmission. I changed his calibration and was not able to get rid of the flare but then after a couple of tries on the valve body was able to completely nail the 3-4 shift at wot.
Simply opening up the hole for the k3 clutch on the intermediate plate were it bolts to the transmission allowing the clutch to fill faster at lower pressure did the trick. I have some more work to do on how big the hole should be. We ran out of time yesterday. I would like to try a little bigger. Although it does not seem to need it.
Cannot wait to try this on my coupe. This was the last big tuning hurdle I had. The system is just really good now.

This is great news. Ive been toying with the ideal of doing a M113 swap into my w126. And standalone TCU integration has been my only area of concern. I will be megasquiring the current 4.2 m116 for this year, midas well when 90% of the MS parts can carry over. But planning to use the MS3-pro to run the M113 5.4L sc . And with the PCS 722.6 in the works. This will be a wonderful combo!

__________________
Just my MB's:
1990 420sel - Winter DD - 410,000km
1990 560sel - absolutely showroom mint - 360,000km!

Give me a shout whenever you are ready or have any questions.

Hi there

I own a w202 turbo w111
I made some serious numbers with my last setup...
My transmition doesn't seem to good...
I use a manual w203 270cdi 6 speed and want to go Auto
I ve heard that 722.6 can handle serious torque...

Can I go with ur controller? Anything else needed to go from manual to Auto?
I use standalone efi .... Does this system need something more to work ? Does It work on its own? Can I put it on a BMW lets say?can I use paddles to manual shift?

Would be really glad for your response
Thanx ... Theodore

You will need a shifter and a driveshaft at the minimum.
As far as using it with a standalone efi that is no problem. All it needs is shifter status and TPS and Engine rpm. It does require tuning for your specific application and tuning software comes with for doing this.
As far as power capabilities the transmissions very a great deal in the setup inside. For something making high power a good starting point is using a v8 transmission and swap the correct bellhousing to fit your engine. The torque converters are different for the inline engines as well.

Can I use paddles? Does it have something like launch control or something for good 18m on the dragstrip?

You can use paddle shifters but for drag racing you would use the WOT shift tables.
As for launch control that would be something your ecu would do. Automatics do not have lock up rate control like the dual clutch transmissions. You could use a pwm output to reduce power at lower speeds or in lower gears if your ecu will do that.
If you are turbo the other thing to do is to put a multi stage boost controller on. PCS makes a very nice datalogger, D200, with a 15 stage boost control feature. You can make each stage whatever you want for how much boost and what the trigger is to change. So you could have boost per gear, plus boost per mph, plus if wheel slip was above x% to go to a lower boost etc. Almost what ever you can come up with. So you could leave the line at 5lbs of boost and then at 5mph switch to 10lbs, then in 2nd go to 15lbs, and so on.
You can also datalog all the ecu and tcu data from one spot.