Break in time for new engine

Great post, this question has puzzled me for a long time.
When the automakers build an engine there is really no break in period like all the discussions above, at the auto factory the engine is assembled installed in a new vehicle sold and someone drives the car, you never hear people talking about their engine break in period, although if you read the owners manual there is a blurb about the first few thousand miles.
Enjoyed all these post


I used to hear the engine had to be broken in. You took the car back to the dealership after a few hundred miles to have the idle speed adjusted again--least some folks did that. You were to limit the car speed for the first 500 miles and no towing till after 500 miles.

things were really different 45 years ago. You used to sit in your car at gas stations while they pump fuel in your car and checked the engine oil level. At the gas station they would adjust the idle speed if you asked.

I was just a tiny kid but recall seeing all that, then to save money at gas stations full service went away in the 70's--good thing or gas might have kept going up--wait it still did:thumbdow: