Hi, Sajeev. A coworker recently bought a new commuter car. Not some fancy $25K+ sports car (under $20K “sporty” commuter car). He talked about breaking in the new engine hard for the first 120 miles: putting the auto into gears 1 and 2 and redlining it. Driving 0 to 120 to 0 to 120 mph.
Supposedly it makes the engine better. Where does the TTAC community stand on this: easy or hard break in for a new car?
Holy crap! Putting it mildly, your coworker sounds a bit extreme. And extremes are never good on a new engine. Loading the engine at various RPMs ensures piston rings and valvetrain components seal properly. You never want to set the cruise control and take a long drive in a new car. Always vary your speed, or at least go between different gears at the same speed.
That said, I am not a fan of running near redline for the first 200-500 miles. Breaking in a motor means gently coaxing moving parts into their new home, not forcing them in with a jackhammer. I also do not recommend switching to (i.e,. not used from the factory) synthetic oil at this time, let the motor break in first.
This is a very controversial car-care subject, to say the least. So, Best and Brightest, give us your thoughts on the matter.
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