Anyone know whether or not the engines on the mustangs are already broken in? When i bought mine they told me that they are broken in already from the factory (ran for 500 miles)

 

I'm guessing no one heard the same thing when they bought their stangs

 

My dealer didnt tell me anything regarding engine break-in. It is a good idea to vary the RPM's for the first 1000 miles. Dont use cruise control for any extended period.

 

do your normal driving routune .. just dont idle a lot ..

 

I've been driving it easy, and trying to vary the RPM's, just tired of waiting

 

Curious as to why ppl say not to idle it much and to vary the rpms?

I build engines and I just don't see how this will prolong its life.

 

Thats something I have always heard also. Vary speeds on longer trips. I think it has something to seating the rings if I remember correctly .

 

its` been so long since i learned that i dont remember the why of it .. perhaps todays much tighter toleranced engines dont need a so called breakin period ...

 

I think also with the cylinders.

 

Todays engine cylinders are very finely honed. Little if any metal is found in the oil on a first oil change. The rings these days seat really quick. I'm talking a few hundred miles tops. And as far as I know varying rpm has nothing to do with them seating. Heat helps the rings seat. So I would imagine higher rpms would seat them better. But as I stated earlier the rings seat quick now anyways.

 

www.youtube.com/watch?v=G0yTTvh_Ikg

here is the Eco boost. several video series on YouTube. no breaking from the factory. put straight to abuse. at the end they do an engine teardown and all the clearances are still within factory specs.

 

That's crazy. Good to know though because i've been taking it real easy on the engine during the break in period and am tired of waiting haha

 

Who told you to drive it easy, don't do that during a break in?

 

As in not accelerating hard, but i've been making sure to alternate the rev's. I hearf mixed things such as drive it as u normally would or take it easy until 1K.

 

I buy one. And I spin the tires coming off the lot

Grandpa bought one several years ago. Took it sideways out of the dealer. Then went to the dragstrip with 350 miles on the odometer. He is now at 55000 miles with no issues. So I say the break in theory is false.

 

Lol yeah i've been hearing mixed things about it. Biggest thing was that the dealer told me that the engines were already broken in before from the factory. Wanted to see what you guys heard

 

I hear mixed stuff all the time, but same with all engines, just vary rpm. Another good way is when coming to a stop, downshifting and having the engine take the load (I.e. rpms going up as u downshift)

 

One of the Mustang racing teams posted here once that took their brand-new 5.0 engines, drop them in the race car, and they've been at 5,000-7,000 rpm's ever since with no problems!

Now THAT'S a break-in!

 

Just like my chain saw and leaf blower full throttle allllllll the time

 

The sales manager at my Ford dealer told me that my new 2009 GT/CS was ready to run hard. So, that's what I've been doing since day one. Just never brought it to redline for the first 600 miles. No issues. Not a good idea to pamper any new car for the first few hundred miles.