Greetings Mr. Kilmer and Techsus,

I hope all is well. I have a 2009 Mercedes C300 that vibrates somewhat roughly at idol (and sometimes briefly vigorously). When it's cold the transmission jerks and the RPM jumps slightly when changing from 1st to 2nd gear (but this stops after the car warms up), and when the engine is warm every now and then it I will hear a clunk and feel a jerk when its down shifting. I saw your video where you spoke about the torque converter, could this be an issue?

Thanks, Pendelton King

Comments
No. 1-2
Pendelton King
Pendelton King

Last time I took it to the dealer was for an alignment but they told me about something in the transmission transfer case. I haven't taken it to AutoZone yet but I had recently put a new battery in the car last summer. Yesterday I noticed that it was running a little better, however it should be noted that I've been driving it more than usual this week. I bought the car used so I am unsure when the last transmission fluid change was. I did have the engine oil changed in November of last year an the only thing my backyard mechanic noticed when he drove it was a slight shaking sometimes when moving from a stop. No fault codes came up.

Techsus
Techsus

Run a Dealer-level OBDII, incl. Mode-6 and highway driving Live data scans. What fault Codes show up in live or history? When is last time you had transmission fluid changed? Just got good measure, ask AutoZone to Load Test battery-alternator-starter for "free." What all do you find?