I've had good luck so far with this 855T I bought last month. I'm waiting to see how it makes it through the winter here in Mass. So far I've done some pretty basic maint to it such as plugs, wires, dist cap and rotor, replaced the vac elbow by the t-stat housing and cleaned the throttle body and erg vlv. The second day I had it I did the timing belt.

My question is how or what I can do for the lifter noise it makes right after a clod start up. My 97 854R does it after it's sat for a few days or more but even then it almost instantly goes away. The 94 does it for a good 4 to 5 miles from home. In looking around the other forums and what I've read, I should have concern over the RMS with regard to just switching to Mobil 1.
Or should I? What about slowly switching over by introducing one more qt of synthetic until I'm up to doing a full Mobil 1 oil change? What about an engine clean up using either AutoRx or Seafoam? Does any one have any other related experiences in cleaning up a high mileage 850 motor, (169K in my case), with good results?

Thank you