97 E320 Is My Transmission Finished?
 

When I purchased the car the oil in the transmission was milky color (possible water in transmission)

Transmission was flashed and oil filter and oil replaced, there were no any metal shavings or anything strange in it.

The code read by the mb dealer was a speed sensor and adaptation values to the maximum. Dealer suggested that transmission is finished and has to be replaced.

It would shift from 1 to 2-nd very harsh and not shift to 5-th gear and also had a big bang while comming to a comlete stop.
This was in S mode.

I was driving the car for a few months in W mode as it was shifting from 2-nd to 4-th gear very smooth and I do mostly city driving.

J knew that one day I might have to replace the transmission, so I was driving in W mode and hoping it will fix itself.

Recently I started to drive the car and check engine came on and it will not shift to the next gear.
I connected the obdII AND IT CAME UP WITH THE FOLLOWING CODES :
P0715 INPUT/TURBINE SPEED SENSOR CIRCUIT MALFUNCTION
P0720 OUTPUT SPEED SENSOR MALFUNCTION


The car has approx 18K miles right now.

Is my transmission finished or can some parts be replaced to get it going again?

Your help is greatly appreciated

are you the first owner ? i see your sig. mentions 18K on the car. how did this happen at such low mileage ....

The water issue is deadly, but the codes indicate that you could very easily have a conductor plate problem. They conductor plate is basically the internal wiring harness of the transmission. It also has the turbine speed sensors built into it.

It is rather cheap and accessible without removing the trans. Unfortunately if the water has delaminated the clutch material which is typical then you are still up for a rebuild.

If that is the case you should deal with it sooner than later if you have a competent local rebuilder. There are a number of improvements you would get by buying a rebuilt from MB: VB, bearings between the internal shafts instead of bushings, but the units we have rebuilt have had no problem if the bushings were intact and were less than half of MB price. If you take the thing to meltdown you won't have a choice.

BENZ 300 - I belive I am the second owner

STEVE - I hope the clutches are ok as there was no dirt or any materials on the bottom of the oil pan when dealer replaced the oil and oil filter.

I am planing to change the conductor plate, what should I know before attempting this procedure.?

Thank you

I would not drive the car until you find the water contamination; the most likely cause is a bad radiator. Adaptation values to the maximum means the clutch pack are worn. You may need a rebuilt sooner rather than later. If you are going to change the conductor plate also buy the protective covers for the solenoids. To remove the cover you have to remove the solenoids, mark them so you will know were they go. Change the o-rings on them, also change the control valve pressure spring in the valve body # 140 993 58 01.

Lock up solenoid Y3\6y6 A140 277 00 35
2-3 shift solenoid Y3\6y5 A140 277 01 35
1-2\4-5 shift solenoid Y3\6y3 A140 277 01 35
3-4 shift solenoid Y3\3y4 A140 277 01 35

Great info

I removed the valve body, everything looks super clean, no contamination of any kind.

Where does the control valve pressure spring in the valve body # 140 993 58 01 go in and how do I replace it?

Great info

I removed the valve body, everything looks super clean, no contamination of any kind.

Where does the control valve pressure spring in the valve body # 140 993 58 01 go in and how do I replace it?

Is it possible that the 1-2\4-5 shift solenoid is bad as the tranny did not want to shift to 5-th gear and very harsh from first to 2-nd.?

How can I identify the solenoids as to which one is for which gear sgifting ?

How can I check the solenoids if they are good or bad ?

How can I check the cluthes withot taking the transmission apart or it is impossible?

Is there anything alse that I should check or replace?

I am attaching the picture of my valve body for you to see.

Thank you very much

This site has 722.6 description:
http://www.carsoft.ru/avtorepair/akp.html
The site is in Russian, but scroll down and Mercedes 722.6 tranny manual is there in English. It looks like it was taken from the MB training CD.
Reg. Mike

myarmar

Absolutely great site, alot of info there, I am reading now all possible info.

I will probably have more questions later.

Thank you

How can I test the solenoids if they are good or bad, and if bad can they be ordered from the dealer?

Update

I removed all solenoids and they all look good, but please can someone confirm to me if they are good.

I measured the resistance of them and it is as follows:

Y3/6 y6 PMW solenoid valve(torque converter lock-up : 2.5 OHM

Y3/6y5 2-3 solenoid valve : 4.1 OHM

Y3/6y3 1-2/4-5 solenoid valve : 4.1 OHM

Y3/6y4 3-4 solenoid valve : 4.1 OHM

Y3/6y1 modutating pressure regulating solenoid valve : 5.1 OHM


Y3/6y2 shift pressure regulating solenoid valve : 5.1 OHM

Do I need to replace any of them or are they all good to transfer to the new conductor plate?

Thank you

The readings are right. Turn the valve body 180degs, the 4 solenoid should face you, carefully remove the bolts from the plate on your left side, the spring is in the 3rd hole from the left. Post a picture. I am off the work.

Hi

I am attaching a picture of the valve body.

I talk to the parts department and they tell me that valve body is available as a unit and not seperate parts are available - springs etc, not even o-rings.

I ordered the conductor plate , adapter plug connector and 2 filters that go under 2 pressure solenoids.

Thank you for your help

The part numbers I gave you are the right ones, I call my local MB dealer, the spring is available for $20, talk about inflation. I buy them from sonnax thru my distributor. At lest check the spring, make sure it is not broken. Push the VB back to expose the plates.

I can check the spring but where is it exactley?