rwolff
Veteran Member
My car will be eligible for emission testing late this fall (needs it before late next fall, but the certificate is good for a year and I don't want to wait for the last minute), and since it burns a fair bit of oil (classic Mitsubishi 4-cylinder valve seal issue) I want to cut the unburned hydrocarbons when I take it in for testing.
Normally I run a cheap 10W30 dino oil, but my mechanic says that synthetics burn cleaner (in engines that burn oil), and it'll burn a bit less with a slightly thicker oil. The owner's manual lists 10W40 and (not for extreme cold weather use) 20W40 as acceptable grades, so I figured that 15W40 should be a good compromise. 2 years ago, however, I found that my mechanic's supplier didn't carry a 15W40 synthetic (not surprising, since my mechanic deals with gassers).
What is a good 15W40 synthetic that is readily available in the Toronto, Canada area, and has an "SG" or better rating? I've seen some 15W40 (dino) oils that didn't have any "S" ratings (only "C" ratings). Also, if a 15W40 synthetic doesn't have any "S" rating, but has a current "C" rating (such as CI-4), is it likely that it wouldn't meet "SG" standards, or just that they didn't bother with the extra testing because they didn't think anyone with a gas engine would want it?
Normally I run a cheap 10W30 dino oil, but my mechanic says that synthetics burn cleaner (in engines that burn oil), and it'll burn a bit less with a slightly thicker oil. The owner's manual lists 10W40 and (not for extreme cold weather use) 20W40 as acceptable grades, so I figured that 15W40 should be a good compromise. 2 years ago, however, I found that my mechanic's supplier didn't carry a 15W40 synthetic (not surprising, since my mechanic deals with gassers).
What is a good 15W40 synthetic that is readily available in the Toronto, Canada area, and has an "SG" or better rating? I've seen some 15W40 (dino) oils that didn't have any "S" ratings (only "C" ratings). Also, if a 15W40 synthetic doesn't have any "S" rating, but has a current "C" rating (such as CI-4), is it likely that it wouldn't meet "SG" standards, or just that they didn't bother with the extra testing because they didn't think anyone with a gas engine would want it?
