I once owned a 1989 Honda Civic with the 1.5L SOHC engine. Even when new, the engine made a faint knocking noise during the warmup phase. I didn't think much of it at the time since my roommate's Civic of the same year made the same noise, as did other Civics of that era. I changed the oil faithfully at the recommended interval (6000 miles as I recall) using Mobil-1 5W-30 exclusively. I drove the car moderately and maintained it well over the years. By 135K miles the knocking noise at startup had become quite loud and didn't go away until the engine reached operating temperature, which could take 20 minutes in the winter time. Near the end to protect the engine I would let it warmup several minutes and drive gently until completely hot, which could take a while even in the summer. I estimated the noise was caused by piston slap, which resulted from wear of the piston skirt and/or the cylinder wall. Since there was never significant oil consumption and the engine delivered full power, I figured the cylinder wall and rings were not worn. So that meant the piston skirts were worn. But how could there be significant wear using Mobil-1 in moderate passenger car duty with regular oil changes? Maybe those criticisms that Mobil-1 was weak on wear protection (I am thinking of Amsoil's ads showing Mobil-1 to fare poorly on the 4-ball wear test) were on to something? I can't help but wonder whether my Honda would have lasted longer with petroleum oil? Did the Honda pistons have a design flaw? Or did the Mobil-1 oil film drain off the piston skirts so quickly after shut down and cause the sliding surfaces to be dry on cold starts?
Twenty-six years later, now that I have a new car I wonder whether it makes sense to sign up for an oil warranty to cover a potential situation like this? I should have been covered for the piston slap issue. However the warranty terms for Castrol, Valvoline and Pennzoil do NOT cover cam chain tensioners. In my opinion these are more likely to fail first after 100K miles, not piston skirts. So the odds of a reimbursable claim are so low, that an oil warranty is not worth the headache of keeping track of receipts, sticking to one brand for 10-15 years, foregoing occasional sales on competing brands, and changing the oil prematurely to comply with the terms of the warranty when the oil is plenty capable of going longer.
Any thoughts?
Twenty-six years later, now that I have a new car I wonder whether it makes sense to sign up for an oil warranty to cover a potential situation like this? I should have been covered for the piston slap issue. However the warranty terms for Castrol, Valvoline and Pennzoil do NOT cover cam chain tensioners. In my opinion these are more likely to fail first after 100K miles, not piston skirts. So the odds of a reimbursable claim are so low, that an oil warranty is not worth the headache of keeping track of receipts, sticking to one brand for 10-15 years, foregoing occasional sales on competing brands, and changing the oil prematurely to comply with the terms of the warranty when the oil is plenty capable of going longer.
Any thoughts?
