Is New Engine Break In Procedure Still Necessary?

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Fairweatherider

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Do today’s new engines still need a “break-in” procedure? Or just drive it normally and do the first one or two oil changes early?
I’m interested in what the GM owner manual suggests and also what real world engine builders/mechanics think.
I’ve read some guys say that “taking it easy” for the first 500 miles just glazes the cylinders and doesn’t let the rings wear in properly or fast enough. The theory is that you should drive it hard and vary the RPMs right from the start (after reaching full operating temperature of course).
What do you all think? Is new engine break-in a thing of the past?
 

Joseph Garcia

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This is a good question, but unfortunately, I do not have the answer.

The last new vehicle that I had was a 2015 Honda, and I changed the oil early, based on traditional engine break-in theory. I was reprimanded by the dealer for the early oil change, stating that the first batch of oil in the engine was a special break-in blend of oil that was designed to go the full mileage until the first oil change. :banghead:

Let's see what other folks have to say here.
 

Marky Dissod

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Do today’s new engines still need a “break-in” procedure? Or just drive it normally and do the first one or two oil changes early?
I’m interested in what the GM owner manual suggests and also what real world engine builders/mechanics think.
I’ve read some guys say that “taking it easy” for the first 500 miles just glazes the cylinders and doesn’t let the rings wear in properly or fast enough.
The theory is that you should drive it hard and vary the RpMs right from the start (after reaching full operating temperature of course).
What do you all think? Is new engine break-in a thing of the past?
I'd be willing to bet lots of money that I don't have, that GM does not bother with 'break-in' motor oil,
they just use a Mobil1 factory fill that anyone could find at any auto parts store.

If that's the case, then, simply because I'm an overcautious pessimist,
I'd look up the break in procedure for GM's LT4, and use that.

Actually, if it has Engine Confusion (DFM), I'd entirely avoid this feature and drive in L9 during the break-in.
Soon as you can find a DFM disabler (or even a minimizer), I'd install it pronto.

Don't forget to change the ATF & differential fluids after their break-ins as well.
It's an opportunity to find and use other upgraded fluids that would still be warranty-approved.

Do your very best not to drive at any engine RpM or road speed 'constants'.
The more variable you drive it, the better the break-in. Push it, but don't shove it - be sensibly aggressive.
I'd keep it under 4750RpM til after the 1st oil change.
 

jfoj

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Best thing you can do is do not take short 15 minute trips, depending on the outside ambient temp the engine oil in these engines can take up to 30 minutes to match the engine temperature.

Even a 4-8 mile vehicle will have fuel in the oil. Pull the dipstick and check and smell for yourself.

I would try to get the vehicle on the highway for a 45 minute drive to fully warm the engine oil.

If you are getting a 6.2l run Premium fuel in it.

Thing to consider
 

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