New car break-in

This is for the current Camaro SS. I think a lot it is more for the rear diff and brakes than anything else.

Follow these recommended guidelines during the first 2 414 km (1,500 mi) of driving this vehicle. Parts have a break-in period and performance will be better in the long run. . Avoid full throttle starts and abrupt stops. . Do not exceed 4000 engine rpm. . Avoid driving at any one constant speed, fast or slow. . Do not drive above 129 km/h (80 mph). . Avoid downshifting to brake or slow the vehicle when the engine speed will exceed 4,000 rpm. Do not let the engine labor. Never lug the engine in high gear at low speeds. With a manual transmission, shift to the next lower gear. This rule applies at all times, not just during the break-in period. . Do not participate in racing events, sport driving schools, or similar activities during this break-in period. . Check engine oil with every refueling and add if necessary. Oil and fuel consumption may be higher than normal during the first 2 414 km (1,500 mi). . To break in new tires, drive at moderate speeds and avoid hard cornering for the first 322 km (200 mi). New tires do not have maximum traction and may tend to slip. New brake linings also need a break-in period. Avoid making hard stops during the first 322 km (200 mi). This is recommended every time brake linings are replaced. . Should the vehicle be used for racing or competitive driving (after break-in), the rear axle lubricant must be replaced before hand.
 
After 40 years of driving cars I still don't understand the concept of engine break in. Here is my argument. Whether I drive 50 or 70 or 10 mph, the pistons are still moving up and down in the cylinder. Won't the rings seat no matter what? If I am super gentle, I get that it will take longer, but so what. Are not the rings still going to seat? What am I missing?
 
Here is what it said for the Z28s and the Trans Am

Your vehicle doesn’t need an elaborate “break-in.” But it will perform better in the long run if you follow these guidelines: Keep your speed at 55 mph (88 km/h) or less for the first 500 miles (805 km). Don’t drive at any one speed -- fast or slow -- for the first 500 miles (805 km). Don’t make full-throttle starts. Avoid making hard stops for the first 200 miles (322 km) or so. During this time your new brake linings aren’t yet broken in. Hard stops with new linings can mean premature wear and earlier replacement. Follow this breaking-in guideline every time you get new brake linings. Don’t tow a trailer during break-in. See “Towing a Trailer” in the Index for more information.

I have never seen anyone break in a Sports/Pony/Muscle car like that. That statement goes out the window on the first test drive and lot of those cars don't live an easy life. Certainly not the life of a Camry or a Malibu.
Honestly, “most”people I know have always been somewhat careful after purchasing a new vehicle. After 1,000 miles the newness mindset wears off and that’s when people start being more comfortable with driving the vehicle as they see fit.

To take a new Camaro, Mustang, etc. and take it to the drag strip or dyno machine with only a few hundred miles is definitely the exception, not the rule.
 
After 40 years of driving cars I still don't understand the concept of engine break in. Here is my argument. Whether I drive 50 or 70 or 10 mph, the pistons are still moving up and down in the cylinder. Won't the rings seat no matter what? If I am super gentle, I get that it will take longer, but so what. Are not the rings still going to seat? What am I missing?
You’re missing how the role of vacuum pressure places different loads on the valve stem seals and piston rings.
 
You’re missing how the role of vacuum pressure places different loads on the valve stem seals and piston rings.
But a vacuum situation is going to happen during normal driving anyway. I guess my point is, if I just drive the car as I do everyday, it's going to get broken in.....maybe slower, but it will break in....right?
 
But a vacuum situation is going to happen during normal driving anyway. I guess my point is, if I just drive the car as I do everyday, it's going to get broken in.....maybe slower, but it will break in....right?
The theory is there is only a certain amount of time parts have to wear in together. There is a lot to be said about varying the engine speed. Even Chrysler recommends brief wide open throttle events, mind you they even recommend this on their minivans. Letting off the accelerator after a wide open throttle event is going to create a manifold vacuum pressure that cannot be replicated by just putt putting around at low rpm.
 
Back in ancient history the carbs were installed at the vehicle assy plant (at least at GM) so the finished engine was hooked up to a propane feed plate on the intake and they ran it up to redline on a dyno. If no parts came flying out, it was good to ship. By the 90s they were running them with electric motors, watching the torque signature to see if anything was awry. Not sure what the engine plant looks like today, I'm sure they're even smarter.
 
"The theory is there is only a certain amount of time parts have to wear in together"

That about says it all right there doesn't it? Your engine has plenty of "time".....an absurd argument and why I don't belieive "break in" amounts to a hill of beans.
 
But a vacuum situation is going to happen during normal driving anyway. I guess my point is, if I just drive the car as I do everyday, it's going to get broken in.....maybe slower, but it will break in....right?
IIRC the theory was that addional ring sealing would occur under engine breaking (i.e. in gear off throttle). That obviously can't happen with an automatic transmission set in "D".

In any case I wonder if it's even possible to seat the rings with the introduction of plasma arc cylinder liners.
 
"The theory is there is only a certain amount of time parts have to wear in together"

That about says it all right there doesn't it? Your engine has plenty of "time".....an absurd argument and why I don't belieive "break in" amounts to a hill of beans.
Apparently, for some engines, when it comes to seating the rings you get one chance (first 10 miles or so).

I only have my own anecdotal experience. The only engines which didn't burn oil were ones where I broke them in with only a couple of miles on the odometer.

May not even be relevant today.
 
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Honestly, “most”people I know have always been somewhat careful after purchasing a new vehicle. After 1,000 miles the newness mindset wears off and that’s when people start being more comfortable with driving the vehicle as they see fit.

To take a new Camaro, Mustang, etc. and take it to the drag strip or dyno machine with only a few hundred miles is definitely the exception, not the rule.
I'll provide this as I think is speaks to how good modern drivetrains are.
I was thinking about the police cruisers. I am in a few Caprice PPV groups. Lot of the cars that were in service now have over 100,000 miles on them with 7000 to 12000 engine hours. Half of that at idle. There are a few officers who bought back their old cars when they went to auction. The collective asked about break in, they laughed. The one guy said he got his car with 200 miles on it and it was hammered from day one until it went to auction.
 
I did the easy kind of break in on my 98 chevy K1500 after I bought it new and it has always burned a little oil.

On my 2014 Mustang GT, I did several hard pulls and then let the engine decel on it's own and it doesn't burn any oil.
Two vehicles from two different mfgs. built over a decade apart. If I had to venture a guess I'd say it was probably the luck of the draw, vs. how you broke them in. I try to do a more agressive break in like you did with the Mustang, and a couple of early oil changes
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on a new vehicle. I know a lot of people who just bought their cars and drove them with no break in. Some burnt oil, others didn't. This is another hot topic on Bitog with a lot of different opinions.
 
Two vehicles from two different mfgs. built over a decade apart. If I had to venture a guess I'd say it was probably the luck of the draw, vs. how you broke them in. I try to do a more agressive break in like you did with the Mustang, and a couple of early oil changes
27.gif
on a new vehicle. I know a lot of people who just bought their cars and drove them with no break in. Some burnt oil, others didn't. This is another hot topic on Bitog with a lot of different opinions.
At the end of the day with a new car new motor ......

Just drive it !!

All will be ok !!!👍
 
The only new car I've ever had was the '75 Ford Maverick. I was so new to driving that break-in didn't occur to me, and I don't remember if there was any instruction about it in the manual. All my cars since then have had 30K or more on them -- the W126 had 130K. The Maverick never burned oil that I recall.

Oh, wait, there was the '84 Ford Escort. Full throttle on that little 4-cyl. was something I avoided, because it made noise but didn't make me go any faster.
 
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Two vehicles from two different mfgs. built over a decade apart. If I had to venture a guess I'd say it was probably the luck of the draw, vs. how you broke them in. I try to do a more agressive break in like you did with the Mustang, and a couple of early oil changes
27.gif
on a new vehicle. I know a lot of people who just bought their cars and drove them with no break in. Some burnt oil, others didn't. This is another hot topic on Bitog with a lot of different opinions.
It's hard to say if there is any correlation in how you break in a vehicle and whether or not it will use oil early on.

The reason I broke the Mustang in like I did was that most of my research at the time on breaking in an engine on a new car pointed to several hard runs and then let the engine compression brake down was the best way to ensure that the rings were seated in case they hadn't from whatever the manufacturer had done.
 
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