Rant: I called Seafoam snake oil for 10 years, then my $700 Buick started knocking on I-70
Two sides here. Some guys swear a $12 can of Seafoam in the oil and gas will fix a rough idle and a stuck lifter, and other guys say it is just kerosene with a pretty label that does nothing but lighten your wallet. Last week my 2001 Buick started knocking at 186,000 miles just outside of Columbia, Missouri, so I dumped half a can in the crankcase and half in the tank out of pure desperation. The knock got quieter in about 40 miles and the idle smoothed out by the time I got home, which honestly annoyed me more than if it had done nothing. Now I don't know if it actually cleaned anything or if I just got lucky, so somebody tell me if you have seen it work or if I wasted twelve bucks on placebo.
Ran a can through the oil on a 4.3 Vortec that had lifter tick so loud you could hear it over the radio. Took about 60 miles but it shut up. Could be the fresh oil doing the work though, since you gotta change it after anyway. That part always gets left out when guys swear by it. Pour it in, drive a bit, then dump the oil. Kind of feels like the oil change is the real fix and the can just gets the credit. Still, 12 bucks is 12 bucks.