: Why exactly do you get better gas milage after 2000 miles

08-18-10, 07:12 PM
Can anyone tell me exactly why you suddenly get better gas milage after say 2000 miles. What happens. I always was told this but I never new why especially with the newer better engines

08-19-10, 05:54 AM
Even with the closer tolerances of todays engines there is a certain amount of break-in and matching of new parts together. As the engine gets some time on it the parts start working together and actually loosen up (just a bit) and friction is reduced and mileage increases. And the loosening of parts is not limited to the engine; all the driveline parts break-in as well.

08-20-10, 12:25 PM
Also, mileage increases with well, mileage. As you drive for longer periods of time in the same RPM range, it creates a sweet spot for RPM, returning the best mileage in that sweet spot.

Yey for highway stars! :D