I changed this oil early due to annoying valvetrain ticking noise at hot idle. The engine was neglected by the original owner, long 22K-25K mile OCIs with unknown quick-change place oil according to CarFax. I switched back to Pennzoil High Mileage 5W-30 conventional oil, and the hot ticking noise was gone. I'm running 640:1 TCW3 in the gas every tank and have been since ~178K miles.
Thoughts are invited. My observations:
1.) No significant increase in wear metals accompanying the ticking noise;
2.) Flashpoint depression is interesting. Long Term Fuel Trims are balanced at -1.56% on both banks at hot idle, and remain balanced to within +/- 0.78% during acceleration and cruising, no puff of exhaust smoke on startup...no indication of fuel injector leakage.
I did this oil change after a cold start and quick 2mile drive to warm it up, whereas the previous oil changes were fully at operating temp after the ~35 mile drive home from work.
I have no explanation for the hot idle ticking noise...plenty of moly in this oil, thickest 100degC viscosity I've used thus far, but the old 211K mile engine just didn't like it.
Previous oil sample was Valvoline Synth High Mileage 5W-30 D1G2, no audible ticking noise but the windows were up and I might not have heard it. Samples before that were either Pennzoil High Mileage conventional, or PP High Mileage, except for the first sample which was old Amsoil SS 0W-30 with a bottle of Lubegard moly additive.
Thoughts are invited. My observations:
1.) No significant increase in wear metals accompanying the ticking noise;
2.) Flashpoint depression is interesting. Long Term Fuel Trims are balanced at -1.56% on both banks at hot idle, and remain balanced to within +/- 0.78% during acceleration and cruising, no puff of exhaust smoke on startup...no indication of fuel injector leakage.
I did this oil change after a cold start and quick 2mile drive to warm it up, whereas the previous oil changes were fully at operating temp after the ~35 mile drive home from work.
I have no explanation for the hot idle ticking noise...plenty of moly in this oil, thickest 100degC viscosity I've used thus far, but the old 211K mile engine just didn't like it.
Previous oil sample was Valvoline Synth High Mileage 5W-30 D1G2, no audible ticking noise but the windows were up and I might not have heard it. Samples before that were either Pennzoil High Mileage conventional, or PP High Mileage, except for the first sample which was old Amsoil SS 0W-30 with a bottle of Lubegard moly additive.