Slight "knock" in first gear

[lunatic]

3 litre engine and 5-speed automatic transmission. 100,000 kms on odometer. Sometimes when starting off from a standing start in first gear, there is a slight "knock". It feels like it is coming from the driveshaft.

No other issues with engine, transmission noise at all. All gear changes smooth. Rolling start no issues. No slipping between gears.

Could this be a transmission problem or something else expensive? Maybe the teeth on first gear in the transmission?

Any ideas? Thanks.

[Vtxbe]

if it's occur when you disengage P and if the vehicle is immobilised in a hill without handbrake, its is normal but not happy
To avoid it, use handbrake before engaging P mode
If it's occur when D mode is engaged, no idea... check suspension be certain the bodywork does not balance in case of "hard" starting.

note: donn't hesitate to change the oil of the gearbox; follow guide lines of Mercedes

[lunatic]

I noticed it when the camper is in DRIVE at traffic lights. When starting there was a slight knock. Sounded like it came from underneath. It seems like the sound a driveshaft link would make when engaging.

I will get the transmission oil changed.

I just hope that it is not a transmission issue..................

Thanks.

[rainerd]

I would say it is normal. Will observe this when I drive tomorrow and give you feedback

[lunatic]

Thanks Rainerd, I appreciate it.

[rainerd]

When starting rolling in D evertyhing is smooth, no knocking. Only when switching from P to D like vtxbe described. Let a mechanic check it but I doubt that it is a transmission issue.

[lunatic]

Thanks for the feeback.