Guys I have a 1999 mazda protege with a 1.8l in it with 198000 it is my work car, I drive it everyday 60 miles back and forth to work the car don't leak a drop but it was using 1qt in 3k. I have been running PYB 10w30 and wix filter. The engine is a little noisy at start and puff of smoke the fine all day. I change to Pennzoil HM and purolator oil filter Pureone. Now with 3 weeks on the oil change the engine is quite at start and no puff of smoke. I used pennzoil 10w-40HM hat is all the part store had in stock, Is the oil or the filter to blame for the for my good fortune? Do you guys think 10w-40 is too thick?? I have noticed that wix filters on this car does leak back after the car sets for a day or so it has not done this with the purolator Pureone..