Issue with the gearbox of the Mercedes W211 E270

[motorman3]

Greetings, I want counsel concerning the transmission of my E270 CDI. Below is a comprehensive account of the issue along with pertinent facts that may assist.


Vehicle Identification Number (VIN): WDB2110161A309273
Transmission: 722.640 (variant 04)




The issue:

When the gearbox is cold, the 1–2 upshift might be excessively abrupt and occurs prematurely, approximately at 1600–1700 RPM.


However, when the gearbox reaches a temperature of approximately 80–90°C, I have a distinct issue between 2nd and 3rd gear. As the vehicle nears 2000 RPM, the RPM begins to increase autonomously, suggesting a potential loss of hydraulic pressure or slippage in the gearbox, even in the absence of further throttle application. The RPM experiences a little spike and varies for around 2 to 3 seconds until the gear ultimately engages.


The gearbox is unable to maintain pressure or execute a seamless 2–3 shift until it "catches" and finalises the transition.


The ATF was replaced 500 kilometres ago, along with a new filter and connecting plug.



My enquiries:

Should I disassemble the gearbox to examine the valve body or clutch packs, or is it more prudent to seek a quality used 722.640 unit?
Which transmissions are compatible with my vehicle?
Is my vehicle exclusively compatible with the 722.640 gearbox from the 2.7 CDI?
Are transmissions from other engines (2.2 CDI, 3.2 CDI, petrol engines) compatible?
If they are physically compatible, are they also electronically and hydraulically compatible?

Any guidance or insights would be very valued.
I appreciate your assistance in advance!

[BENZE220AMG]

When did the difficulties commence? Prior to or subsequent to the ATF modification? Is a reputed oil brand utilised? Is the oil level verified twice? Is the TCU and connecting plug devoid of oil?

[motorman3]

The gearbox exhibited this issue prior to the fluid change.
I utilised authentic Mercedes ATF and added a new genuine Mercedes connector plug.
Transmission fluid was present within the previous plug.

The gearbox pan utilised non-OEM bolts, and the drain bolt was stripped, indicating that an inexperienced individual had previously serviced the gearbox before my acquisition of the vehicle.
I have possessed the vehicle for around one year.

[motorman3]

The ATF level is accurate and has been verified.
The mechanic who conducted the most recent inspection of the vehicle informed me that there is certainly an issue with the valve body, and it is quite probable that there is also deterioration in the clutch packs.
This remains a possibility, as the vehicle has not undergone live data diagnostics; nonetheless, based on the symptoms, multiple individuals have indicated that repairing this gearbox may not be economically viable.

[motorman3]

Numerous friction material deposits were present at the bottom of the pan; however, the mechanic who replaced my ATF and filter reported that the interior of the gearbox appeared pretty clean.

[motorman3]

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