Topic!

Have the Crossfire, which has the same transmission, brakes, engine (practically everything) as the 1999-2003 SLK 320.

In second gear, just shy of 5000 RPM's (I take it up that high when merging), the shifter makes a fairly loud vibrating noise, and much to my horror, can be easily shifted out of second gear at that point without touching the clutch whatsoever, which was discovered when I grasped the handle and was about to shift (had not touched the clutch), but the relatively low pressure of my hand being on the shifter was enough to take it out of second gear...

This is not good.

Any ideas?

 

all stick shifts ive driven can be pushed out of gear fairly easily without the clutch, i dont think thats a problem.
your vibration could be motor mounts and trans mount.

 

I've never had a stick before that could be 'pushed' out of gear without the clutch... maybe I've been lucky, or maybe it's been the transmissions that I've had.

The vibrations could be a mount, I hadn't thought of that. I made the connection that if the shifter could pop out that it had to be something related to the linkage and/or bushings.

I'll ask my mechanic to take a loot - see what he finds. The car is seven years old (it's a 2005), but it only has 20,000KM's on it... it just seems odd that mounts would be shot.

 

Tried a quick experiment on the way to work; pushed (VERY gently) on the shifter while in 2nd gear at about 3000 rpms WITHOUT having the clutch engaged - the car kicked right into neutral. Maybe I was matching engine/transmission RPM, but...

Unless really easily coming out of gear is normal in the six-speed, I'm not sure what the problem could be (can't imagine transmission mounts causing this).