300E Transmission!

[AV]

I have a 300E with 135kms on it that i just purchased not too long ago.I dont drive it too often in winter but took it out the other day and it seemed to me that it slipped and the rpm jumped to 4000 and it was going nowhere.This only happened twice when its not warmed up more than 10 minutes and never repeats itself.
The vehicle has been regularly serviced accourding to the books and is in mint shape.Any suggestions?
I did change a radiator a couple of months ago when the neck cracked ..could i have done something wrong ???
Thanks for the input.I know it needs a O2 sensor as the light comes on intermittently and the cover behind the battery seems to be missing.

[This message has been edited by AV (edited 02-03-2000).]

[This message has been edited by AV (edited 05-31-2000).]