Automatic gearbox problem

[ChatMaven]

Hello everyone
I own a 2007 E320 CDi V6 diesel automatic vehicle experiencing a gearbox issue. I would value your insights on this matter.
Recently, the vehicle has been experiencing issues where it would remain in a high gear with reduced drive, similar to a sliding clutch, or become stuck in a low ratio while accelerating. After a brief start and stop of the ignition, everything was functioning well for many hundred kilometres.
Resetting it last night was ineffective, and now there is a sharp engagement when shifting into forward or reverse, similar to my previous Range Rovers, where it engages abruptly.
Any suggestions? We have a few mercenaries who specialise in Mercedes vehicles, as well as professionals in gearboxes.
The automobile has low mileage (110k) and a complete history. I would want to retain it, but not at the expense of purchasing another car.
Any assistance would be very appreciated.
Thank you
 

[bvlenci]

When was the most recent gearbox maintenance performed and by whom?

[ChatMaven]

Mercedes introduced this model 50,000 years ago. It seems unlikely that the issue is related to a simple oil change.

[bvlenci]

An improper ATF level might cause unexpected issues with your gearbox. Inspect the fluid level. At 50,000 miles, you may need further servicing.

For a 7G tronic gearbox, the service should be performed after about 40,000 miles or after 4 years.

[TechWhiz]

Were any unusual warning lights such as ABS or ESP shown on the dashboard? Occasionally, the speed detectors may need replacement and might result in the symptoms seen in the gear box.

Quality service is always valuable. My vehicle is scheduled for a MOT and gearbox repair on Monday, along with the replacement of speed detection devices, which is how I became aware of the gearbox issue.

[dave783]

Do not dismiss engine issues before attributing the issue to the gearbox. Have it scanned for codes. Resetting the ignition would not affect gearbox difficulties, to be honest.

[TechWhiz]

Interestingly, when I reset the codes on my vehicle, I was advised that if the issue reoccurs, I should switch off the ignition, wait for about a minute, and then start the vehicle again. Therefore, I am having the speed detectors replaced. My gearbox has been functioning perfectly once all the errors were cleared. Before that, it was experiencing the identical troubles as the initial poster. It seemed like the vehicle was stuck in 3rd gear and reverse was not engaging, along with other related problems.

Consider exploring the codes and doing a reset to see if there is an other issue at play.
 

[ForumGuru]

Completely agree.