HI Y'all,	
  About that  harmonic vibration that TOBIN@freenet.vancouver.bc.ca 	
mentioned; I read up on that after experiencing the same problem on a	 
long trip to New Mexica last month.  I had just rebuilt the engine right
down to the main bearings and valves.  It was running great the whole two
thousand miles or so.  But toward the end I was hearing that disharmonic
vibration.  Upon returning I found a troubleshooting
table that pointed to  spark plugs.  As a result of using chrome-	
molybdenum  rings (I think), it has taken a little longer for them to	  	
seal against the cylinder walls.  So a little oil fouls the plugs.	
  It's hard to tell which plug(s) are causing the problem, so I	
just replaced all 4 and did notice a difference, especially when in 	
the high end of 2nd or 3rd gear.  I'm thinking of going with the
platinum plugs next time.  
  Happy motoring.		
Chris 
'71 Camper