When I was in grade 10, my auto shop teacher was a huge fan of Mobil 1. He had driven a Jetta to north of 1 million Km, at which point they took it and gave him a new one, or that's how the story goes anyways. He had more than 500,000Km on his replacement when I took his course. He had torn down tons of engines over the years and was quite emphatic about how using a synthetic oil was a superior choice. Now keep in mind, this was back in the "Tri-syn" M1 days, before the Castrol BBB dispute...etc. We are talking early to mid 1990's.
He got me excited about M1, at which point I got my dad using it in everything we owned.
My grandfather stocked cases of whatever he got on sale for our boats. 10w-30, 10w-40 and 20w-50. One year it was Valvoline white bottle, the next it would be Castrol GTX. Seemed to do the job, however I got him on the synthetic bandwagon too with the high dollar engines.
Anyways, when I got my first car, I ran M1 in it and ran it in pretty much everything else since. Of course I've used other synthetics over the years: Pennzoil Ultra, AMSOIL, Royal Purple, Motul, but I always seem to end up back at M1
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