Finally signed up after browsing this site for quite a while. I’ve been tinkering with cars for about 40 years and I eventually came to the conclusion I’d change oil twice a year, mostly because I’m lazy and secondly because it seems to be cost effective. The oils used for these three runs were whatever was cheaply available at the time and I do not hesitate to mix oils. The first test did not contain any synthetics and produced low TBN readings so I included some Group III synthetics in the next two runs. Driving 50/50 Highway City.
The first test [7,500 mi] oil was Canadian Tire [shell] Supreme conventional 5W30 with a bosch filter.
The second test [8,500 mi] oil was %80 Canadian Tire synthetic [shell] and %20 conventional 5W30. I’m not really sure what brand the conventional oil was, perhaps PYB or Castrol GTX. Mobil 1 ext performance filter. During the run .5 quarts PYB was added.
The third test [12,600mi. 3,000 of which was a highway trip] oil was %50 Canadian Tire synthetic [shell] and %50 PYB 5W30. Basic Fram Filter. During the run .8 quarts Valvoline Synthetic 5W30 was added.
Most people here don’t seem to want to exceed 5 or 6,000 miles even though the UOAs they are posting don’t show excessive engine wear and the oil is still good. I don’t think it’s harmful to go further. Too each his own.
The first test [7,500 mi] oil was Canadian Tire [shell] Supreme conventional 5W30 with a bosch filter.
The second test [8,500 mi] oil was %80 Canadian Tire synthetic [shell] and %20 conventional 5W30. I’m not really sure what brand the conventional oil was, perhaps PYB or Castrol GTX. Mobil 1 ext performance filter. During the run .5 quarts PYB was added.
The third test [12,600mi. 3,000 of which was a highway trip] oil was %50 Canadian Tire synthetic [shell] and %50 PYB 5W30. Basic Fram Filter. During the run .8 quarts Valvoline Synthetic 5W30 was added.
Most people here don’t seem to want to exceed 5 or 6,000 miles even though the UOAs they are posting don’t show excessive engine wear and the oil is still good. I don’t think it’s harmful to go further. Too each his own.
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