A chat with an old timer at the truck stop in Flagstaff made me rethink engine break-in procedures.

I was grabbing coffee last week and got talking to a guy who's been running heavy haul for 40 years. He said modern diesels don't need the 500-mile gentle break-in the manuals push, and that a proper load right away seats the rings better. I've always followed the book to the letter, but he had some convincing stories about engines he'd seen last 800,000 miles. What's the real consensus here, gentle run-in or hard run-in from the start?

3 comments

3 Comments

wade_perez10d ago

That "proper load right away" thing is what gets me. I've heard that old school wisdom for years, mostly from guys who ran older mechanical engines. Modern stuff with tighter tolerances and different ring materials? I'm not so sure. The engineers who wrote the book probably had a reason. But then again, I've also seen fleet trucks get worked hard day one and run forever. It's a real coin toss. I still baby a new engine because the "what if" would eat at me.

holly_green8210d ago

Yeah, and that "what if" is a killer. I babied my last new truck like it was made of glass for the first thousand miles. Drove me nuts avoiding hills. Then my buddy, who runs a landscaping business, gets the same model and hauls a trailer full of mowers on day two. His is fine. Makes you feel a bit silly, you know? Like @wade_perez said, it's a total coin toss now. The engineers say one thing, but real world beaters just keep on going. I guess I'd rather feel silly than worry I wrecked it by being too careful.

the_phoenix7d ago

Right? The whole thing feels like a superstition at this point.