I only have 400 miles on this truck and the engine feels very tight. How long does it take to loosen up & is there much of a performance diffrence.

 

Most people start feeling a difference between 2k and 5k miles. Some of us have even noticed changes all the way thru 10k miles.

 

Hi therocknj,

Dennis gave some good advice.

New engines made in the last 10-12 years or so seal much tighter, many use zero-gap piston rings, etc. and the net effect is that it will take anywhere from 4000 to as many as 8000 miles for new engines to fully loosen up & make their rated power & mileage, that's perfectly normal.

There is no break-in period per se anymore, thanks to advances in assembly techniques, metallury & lubricants. So at 400 miles, you can drive it anyway you like, but it's going to take somewhere between 4000 & 8000 miles to see it's best power.

This isn't going to be any "big" difference, though it's enough to be able to feel a little bit for those that are very attuned to their vehicles. In reality, you're only talking about maybe 12-15 hp or so in these V-8 F-150's, and for some people, that's enough to feel.

So as you accumulate more miles, you may notice that it feels a bit stronger, but it won't be a really significant difference.

Good luck with your truck,

------------------
Mike Troyer
Performance Products, Inc.
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(540) 862-9515
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