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Break in?

17Blk350

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If break in were so important, wouldn't all cars in inventory be set to only go up to a certain RPM? I know some salesman give you the keep it under a certain RPM before the test drive, but plenty don't. Furthermore why wouldn't they be set from factory to not go above 4000 rpm until they reached the prescribed mileage? Just my observation.
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nastang87xx

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You are not only breaking in the engine but breaking in the transmission, the driveshaft the diff, the axles and all the rest. There are hundreds of parts involved and it is all breaking in as these are cheap mass produced cars. Nobody is lovingly, painstakingly matching bearing surfaces or any of that. So the parts have to wear together still. But the engine determines how stressed the trany and everything to the rear wheels is treated. So do yourself a favour and take is real easy the first 500 miles and then under 4000 to maybe 1000 - 12000 and then at the end of 1500 try some rolling bursts to 5400 and if that feels right a couple of of redlines and that should be it. Pull the dipstick and pass it on a white sheet and move it around in the sunlight and see if anything sparkles. You may see some tiny bits that would be naked to the eye but show up reflecting in the sun. And that is why you change the oil now at 1,500.

Good to go after that.

My Corvette LT1 motor went 23 years and my 302 V8 (5.0) went 18 years and 375,000 kilometres broken in like this and I’m not about to change (I’m an old fart BTW). The boy racers here who redline it from the dealership are usually the sort that also sell the car after a year or two so they don’t really care about longevity like guys like me do. Someone else gets the decreased engine lifespan or whine from the diff or vibration in the drive shaft...


Just say’in....
Modern cars are strapped onto a chassis dyno and ran through a battery of driveline tests before they hit the shipping yard. One of them being taken to redline. I guess apparently I'm a boy racer then too since I broke my car in at autocross at 200 miles...and bedding in my brakes properly unlike everyone else...and checked the fluids after an assault on its components...and listened for any oddities in the engine, wheel assemblies, and transmission. GT350 owners are constantly bitching about oil consumption. Mine's tight as a drum and doesn't eat oil like crazy. Road America, Milwaukee Mile, 150+ autocross runs a season. Purrs like a kitten and bites like a lion. Just sayin............
 

FranzVonHoffer

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Engine break in is done at the factory. They have a whole room full of engines they cycle for break in. But to [MENTION=32333]Fatguy[/MENTION]'s point there's a bunch of other systems you need to break in. Transmission, brakes, differential and also you want to watch for QC problems that might creep up immediately. I had a buddy of mine that found a series of finger tight nuts holding his intake manifold on during a SC change on a new C6 Z06. That was a startling discovery.
 

youra6

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Break ins are usually ruined anyways by people who test drove the car before you. So I don't see the reasoning behind being gentle with the car.
 

Fatguy

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Modern cars are strapped onto a chassis dyno and ran through a battery of driveline tests before they hit the shipping yard. One of them being taken to redline. I guess apparently I'm a boy racer then too since I broke my car in at autocross at 200 miles...and bedding in my brakes properly unlike everyone else...and checked the fluids after an assault on its components...and listened for any oddities in the engine, wheel assemblies, and transmission. GT350 owners are constantly bitching about oil consumption. Mine's tight as a drum and doesn't eat oil like crazy. Road America, Milwaukee Mile, 150+ autocross runs a season. Purrs like a kitten and bites like a lion. Just sayin............
Fair enough but the racers don’t keep their cars as long as most of us do and they usually can work on the cars and motors. They also replace brakes, bushings, rear gears, better driveshafts, etc. If that is you then go for it. Most people here just want reliable cars with an occasional punch in the throttle. They want a problem free car. They would probably drive the thing gently anyway but a gentle break in does no harm to these people and it is better for them to get to know the car. It will probably wear the parts in better anyway and give them piece of mind that if something does break it was not their fault. I found tiny metal fragments in my first oil change. I always do during break in so until bearing surfaces are manufactured to mate perfectly, you probably would be wise to be gentle at first if you are hanging onto the car.
 

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DukeGaGa

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When in doubt, I follow the owner's manual. If it says 1000 miles, I do 1000 miles, if it says 3000 miles, I do 3000 miles.
 

DukeGaGa

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If break in were so important, wouldn't all cars in inventory be set to only go up to a certain RPM? I know some salesman give you the keep it under a certain RPM before the test drive, but plenty don't. Furthermore why wouldn't they be set from factory to not go above 4000 rpm until they reached the prescribed mileage? Just my observation.
Well, because it is one more thing that will break, costs money to do that, and normal people with no knowledge of this would be constantly calling service asking what's wrong with their car.
 

Fatguy

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Also, that new A10 tranny with all the gears. Does anyone really want to be human guinea pig and trash that thing from the get go. I would really be interested in the long term differences due to type of break in. Love to examine the oil and filter in a gentle and drive like you stole it break in.

As for engine limiters to force a gentle break in. The car could enforce this already so don’t give them any ideas for not following the prescribed break in that could void the warrantee in the future. :lol: :ford:
 

Strokerswild

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1. Warm it up fully.
2. Have fun, but vary RPMs and do some engine braking too for the first 100 miles.

That's how I break in any engine.

Mine got bounced off the rev limiter within the first 50 miles. Runs like a champ, doesn't use a speck of oil.

:headbang:
 

Infidex

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My question isn’t so much about whether it’s okay to stomp on it and have fun - it’s more about would you maintain a constant highway speed for 2 hrs within the first 1000 miles - manual says not to.
I had to drive 2 hours home from dealership on a highway when I got mine, just don't use cruise control and don't be afraid to drop down a gear or two and give it some gas off and on while driving, the key is to work the gears and work the engine through various RPMs, versus a steady rpm for extended times.

As far as breaking in an engine, you'll get a million opinions. Some will say don't baby it, you need to get on it pretty hard and change oil soon, some will say baby it and wait until the dash says change oil, lots of opinions.
 

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tom_sprecher

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Except for exotics, I would have to see some proof to believe that any break in is done at the factory. There is not enough time to heat cycle anything multiple times on a new car and meet profitable production schedules.
 

nastang87xx

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One thing I think we can all agree on is that break in doesn't start until temps have reached operating level. Nor should you start "breaking in" until operating temp, especially if you're going to break in your car like I did.
 

16 GT MM/Auto

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I drive how ever I want from day 1 ...
As soon as you pull the car off the dealer lot, and the fluids are fully warmed up (oil/coolant/transmission) HAMMER IT!! ...
It’s just a ford. Drive it like you steal it.
If break in were so important, wouldn't all cars in inventory be set to only go up to a certain RPM? ...
Break ins are usually ruined anyways by people who test drove the car before you. So I don't see the reasoning behind being gentle with the car.
Good to see there are people on this forum who retain logic and make use of common sense! :thumbsup:
 

Nabush

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On my 17 corvette GS. The tachometer the red line stayed 4000 rpms during the first 500 miles. After that it returned to normal.
The hertz Shelby’s are broken in by the wot system don’t you think. Would not buy a 6 speed auto anyways. Had they waited for the new 10 speed then maybe. They are currently @ $47K. Down from $55K.
Strange I don't remember that when I did the breaking in of mine (17 GS also)...I took it pretty easy first 500 miles (but did the breaking in in mountain roads) and then hammered as much as I can (4400 miles now)
 

itguy08

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Well, because it is one more thing that will break, costs money to do that, and normal people with no knowledge of this would be constantly calling service asking what's wrong with their car.
I dono. It's all done by computer anyway so they can simply alter the shift points and redline and I bet 99% of people would have no clue. The Vette imposes a lower redline during break in.
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