Re: vibration
Reply #2 –
You could be dropping a cylinder. Clogged filter, etc. Have had this symptom on hills with several MBZ diesels. Was primary filter. How is the power on hills? Filters that are starting to clog don't show their hand at first on the flat but wait for higher power applications.
If you are underneath, look for red rust colored dust around any part on the U joint. When they are dry they may leave a tell tail indication. Failure here can be expensive if they come apart otherwise just a replacement.