mjanowich bring this with you as it helped the dealer that repaired my XF, i got it from a MBtech on a MB forum as it is happening with the slk320:

Here is what i got from a MB technician on our AUTOMATIC trans...

MB calls the vibration DRONING... and with this info i will go back to the dealership...


DTB
Date:
March 23, 2006
Order No.:
P-B-27.60/43b
Supersedes:
P-B-27.60/43a dated May 3, 2005

Group:
27
Revision History
Revision
Date
Purpose

3/23/06
Step 1 Updated/Noted Added Following Step 1


5/3/05


Damage Code Updated
-
1/10/05
Initial issue

SUBJECT:
Model 170.466
Model 203.040/065/740
Model 211.065/070/076/082/083/265/282/283
Model 215.374
Model 220.174
Model 230.474/476
Equipped with 722.6 Automatic Transmission
Torque Converter Clutch Rough Engagement and/or Droning/Buzzing

If you receive customer reports in the above model vehicles that during acceleration and/or constant drive there is a noticeable jerk, possibly followed by a droning/buzzing, adapt the torque converter clutch as per the below procedure. This may be caused by a lack of/or inadequate adaptation of the torque converter clutch. This particularly applies in cases where there is less than 6,000 miles accrued on the torque converter or transmission control unit.
1. Read engine coolant temperature out with Star Diagnosis [Cars �� Vehicle Type �� control units �� ME �� Actual Values �� Test engine at idle speed].

Note: Before starting the procedure, the engine coolant temperature must be below 20° C / 68° F.
2. Start the engine (cold start, over-night), select “D“ with the shifter and hold the vehicle at idle speed for 20 seconds by depressing the brake pedal.




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3. Start driving the vehicle between 30-40 mph on level ground using the cruise control. With SDS, observe the engine coolant temperature until the engine coolant temperature has risen approx. 10° C / 18° F.

Warning! Hazardous procedure for one technician alone.
4. Stop driving and hold the vehicle in “D” at idle speed for 20 seconds by depressing the brake pedal.
5. Repeat steps 3 and 4 with each engine coolant temperature increase of about 10° C / 18° F until the operating temperature levels out.
6. After reaching a transmission oil temperature of 80° C / 176° F, continue driving between 30-40 mph, on level ground for 10 minutes cumulatively using the cruise control to maintain consistent engine load.

Note: The following allowable labor operations should be used when submitting a warranty claim for this repair.
In Case of Warranty
Operation: Automatic transmission electronic shift adaptation, perform (27-1046)
Damage Code
Operation Number
Time (hrs.)
Model Indicator (s)
27284 45
27 1046
1.0 hrs.
G4, M9, N5, P3, Q1, Q3, R2, R3, T1, T2, T3, T4, T5, U1, U3, U4




P-B-27.60/43b (March 23, 2006) 2


AND THIS: from our own beloved XFF.ORG member... crossfire-tech:

Re: The last straw. - 01-20-2006 , 01:36 PM


Case Number K95898508
Vehicle Issue Customer Complains Of A Vibration / Shudder When Transmission Makes 1-2 Shift.
Year 2005 , 2004
Model ZH - Crossfire
Engine 3.2L V6 SOHC 18V
Automatic Transmission/Transaxle Model NAG1 (5spd Automatic - RWD - Electronic Shift - TCM)
Category Customer Concern (No DTCs)
System or Component Automatic Transmission/Transaxle
Symptom Shudder, Vibration
Driver Input / Vehicle Operation Acceleration , Steady Speed
Transmission Gear or Shift Involved 1-2 Upshift
Case Verification Technician can duplicate concern even when shifter is manually shifted into 1st gear.
If the ABS module is unplugged, the problem goes away. May have codes set in the ABS for LT and RT front speed sensors. Technician tries another ABS module and problem still exists. The technician can duplicate a similar feel in vehicle when he taps on the yaw sensor.
Technician has verified that the ESP (electronic stability program) is activating and applying the rear brakes causing the shudder/vibration.
Recommendation Replace the transmission control module.
Comments There have been 2 known cases of this same issue where a transmission controller fixed the vehicle.
Modification Date 9/30/04 9:10 AM



so when i became (officially) number three in chrysler's database to have this repair done...the tranny module had some sort of short in it... rendering it useless in deciding what gear to place the car in... they took all the info above and solved the problem swiftly!!!

any other questions... let me know... even if your dealer has to call mine... they can ask for MIKE (service Manager).

good luck

josh