Boy do I feel like a dummy. Aplogies again to the Cummins gods for titling this thread "engine vibration". 2 years ago when the hangar bearing went I had the local Dodge dealer install Precision HD U joints for all the factory ones which were still OK with 200,000 kms to be proactive. I put the drivshaft back in and "assumed" my newly installed parts could not be causing the vibration now. Especially noticing a slight vibration at idle. (which still could be my origonal clutch or pilot bearing at 220,000kms). As a sales manager I taught new reps the meaning of "*** u me" as a good way to get blindsided in a deal and lose. Aparently I need a refresher in what *** u me means! To add insult to injury, my mechanic said if I had not tried to be proactive and left the origional factory u joints in it they would probably be Ok like the origional front shaft ones are still. This is my 4th Cummins (1992, 1996, 2000, 2001) and the 92,96 OEM u joints failed early and often. Not so anymore as my mechanic(formerly a Chrysler dealer technician) says the factory u joints now are good pieces. If I buy those 275 RV injectors I have been thinking about I hope the Cummins forgives me for ever daring to doubt its legendary status for reliabiltiy amongst engines. Thanks for all the suggestions. Leason learned!