Vibration when accelerating
 

Hi,

My '88 300SE has a slight vibration when accelerating from a complete stop. It only seems to happen a certain speed then goes away. It only occurs in 2nd gear and does not happen if I kick it down to 1st when taking off from a stop. There is no vibration in any other gear under any condition.

My transmission was rebuilt at 140K and I recently replaced my engine mounts (exhaust was hitting frame on hard acceleration). I've also replaced the front flex disc. Could it be a bad transmission mount??

Thanks in advance for the advice!!

Paul

my benz had the same thing..the vibration came up at 35 mph and when I got it above 45 it stopped.

mine was the upper control arms and my stabilizer guide rod bushings (warning the part is cheap but the labor is a total of 7 hours) compression of the springs, then a front end alignment now no problems.

what speed does this problem start for you?

benzat
1982 380 SEC

My vibration comes in at about 5-10 MPH and goes away as quick as it starts. Maybe I should describe it more as a shudder than vibration. I think it's more drive train related. Any other thoughts??

my 90 190 E 2.6 does this and I haven't been able to find help on it. mine does it 25mph to 35mph only in third gear. It doesn't do it if I drop into 1st than manually shift up. If anyone or you pjtib know what causes this please post it.

One tech drove it and said live with it. He thought it maybe excess play in the driveshaft splines.

If the tech was speculating on loose driveshaft splines --
 

perhaps you need to make sure that the big nut which holds the flexjoint flange onto the transmission output shaft hasn't worked loose -- that's what happened on a high-mileage '69 220D belonging to a friend of mine and lead to the JBWeld incident about which I posted about 2 weeks ago. But perhaps '90s aren't built that way any more.