Engine Break-in

Absolutely ... some cars with some engines limit engine power and revs for X-number of miles, and I see n reason not to follow a similar break-in routine with any new engine.
 
My last 5 cars were all redlined within the first 50 miles: 16 Spark, '18 Forester XT, '22 Forester, '19 XV, '22 Toyota GR86. None use/used any measurable oil.

Obviously the breakin rules started in the 50's or earlier when machining was a couple generations earlier. You esentially completed the machining that a new car bought today comes with. And of course the manufacturer wants to be conservative. They would like you to run the vehicles at less than 65 forever.

The only think I will say is not to run it near redline for prolonged periods of time where excessive heat could be built up. But after the vehicle has 25 miles or less on it I am not sure there would be any difference.

Obviously we will all do what we do now. I think a "benefit" of early redline is to seat the ring but I have a feeling they are "seated" in the first mire or two. I don't really know.

I remember I had a '69 camaro that I was super careful about btreakin...only vehicle that ever used oil. 1 quart every 1500 miles.

I was referring to a new engine from the factory. (not a crate engine)
 
There is a lot of supposition in that post - “generations” of machining? Rings “seated”? Oil consumption tells you everything you need to know about the engine? You don’t keep your cars long enough to know if you did it right, or wrong. A car that doesn’t use oil at 25,000 miles isn’t impressive in any way. A car that doesn’t use oil at 200,000 miles was broken in properly.

Follow the OM.

They know what “generation” the machining might be and how to “seat” the rings. Do what they recommend and you’ll be fine.
 
There is a lot of supposition in that post - “generations” of machining? Rings “seated”? Oil consumption tells you everything you need to know about the engine? You don’t keep your cars long enough to know if you did it right, or wrong. A car that doesn’t use oil at 25,000 miles isn’t impressive in any way. A car that doesn’t use oil at 200,000 miles was broken in properly.

Follow the OM.

They know what “generation” the machining might be and how to “seat” the rings. Do what they recommend and you’ll be fine.
If a vehicle uses no oil at 35K miles its not gonna start because of breakin issues. There is probably a linear curve of consumption vs age...with modern cars say 1/2 quart/7K miles new and maybe1 quart/7K miles. Like I said 48K miles on my '18 and NO Detectable oil use. Three other vehicles no use at say 35K miles. I like their chances.

Kind of a moot point though except for the Forester. Well see hopefully how it does in another 5 years (if Im alive..lol. ) FWIW i redline (ed) all vehicles frequently. The GR86 probably every day...spimds moce at 7500 rpm!! 5 k miles on it, oil looks like it was changed yesterday. Things could change.
 
Where do all the machining debris, bearing, rod knock recalls fall on break in? How many were done per OM?

How does Hyundai/Kia say it should be done?

I'm in the change oil early on new motor, give it some full load harder acceleration but not beat it to high rpm camp.
 
Does anyone here feel it necessary to follow the owner’s manual requirements for their new car after spending a ton of money on said car?
No. The maintenance minder on my Civic won't indicate the need for an oil change until 10,000 miles, and this includes the first oil change. I changed the oil after 2000 miles.

When breaking in a new engine, or a freshly overhauled one, I drive in an assertive city driving cycle. Accelerate briskly, nothing crazy regarding high rpm or full throttle, no light throttle droning. If driving highway, occasionally apply some load, and speed up and slow down. Basically just normal driving without babying the engine, nor thrashing it.
 
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I can remember when I drove my Corvette home from the dealership and I had to drive it 50 miles on the highway to get home. I kept it at 110 kmh most of the way but I was shifting the transmission from 6th to 7th and 8th gear every 30-60 seconds and I was letting off the gas and coasting often. I drove it pretty gently for the first 500 miles other than one full throttle blast at about 200 miles (I shifted 500 rpm before the redline though)

Go back 20 years prior to that and I bought a brand new 98 Firebird Formula. I did NOT baby that car at all! In the first 50 miles I had already redlined it in the first four gears. I then took at least 4 or 5 of my friends in separate rides where I also went full throttle through the first 3-4 gears. A week later I took it to the drag strip and made about 15 passes. That car was a strong running example, I feel like that hard break in might have just unleashed a few extra ponies 😆
 
If a vehicle uses no oil at 35K miles its not gonna start because of breakin issues. There is probably a linear curve of consumption vs age...with modern cars say 1/2 quart/7K miles new and maybe1 quart/7K miles. Like I said 48K miles on my '18 and NO Detectable oil use. Three other vehicles no use at say 35K miles. I like their chances.

Kind of a moot point though except for the Forester. Well see hopefully how it does in another 5 years (if Im alive..lol. ) FWIW i redline (ed) all vehicles frequently. The GR86 probably every day...spimds moce at 7500 rpm!! 5 k miles on it, oil looks like it was changed yesterday. Things could change.

how about no visible consumption in 5k miles on my '24 car (following break-in procedure and early oil change). Ran conservatively for 50 miles then gradually harder and just before the 1000 mile first change it got redlined through a few gears.
 
I was fortunate as a youngster. My dad bought a new car when I was 8 years old.
An uncle pointed out the sound "of a new engine".
He listed all the smart procedures mentioned in this thread and none of the dopey ones.
 
... .

Obviously the breakin rules started in the 50's or earlier when machining was a couple generations earlier. You esentially completed the machining that a new car bought today comes with. ... .
Al, often stated but this is not generally true. Machining quality and tolerances have been tightly held and scrutinized in production since The Ford Model A. There have been gains in Materials science and specialized alloys and casting.

I would actually say the reverse now applies to most commodity passenger car engines with a Net Build strategy using non selected/ or assembler matched parts in critical positions (think Piston-to-bore). Only incoming material inspection of tolerances is employed.
The No fire wet spin up test booth will catch major mismatchs, errors and damaged parts to a fair degree.

Not everything is assembled with care and attention like a Nissan Godzilla turbo 3.8 V6 or a Corvette Z-06 LT6 DOHC 5.5 liter

Break it in the way you wish. Most of the time it's the luck of the draw. Moly rings and a medium-fine hone make it easy.

- Arco
 
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Go back 20 years prior to that and I bought a brand new 98 Firebird Formula. I did NOT baby that car at all! In the first 50 miles I had already redlined it in the first four gears. I then took at least 4 or 5 of my friends in separate rides where I also went full throttle through the first 3-4 gears. A week later I took it to the drag strip and made about 15 passes. That car was a strong running example, I feel like that hard break in might have just unleashed a few extra ponies 😆
Yep, both my 98 and 01 Z28 were hammered straight off the lot. Had the 01 on the Dyno with 151 miles on it. Track next weekend and it went 12.92 at 110.02 mph with paper tags and about 330 miles on it. I put 160,000 miles on thing never used a drop of oil. I treated the 98 worse ran that that up to 156,000. Never used any oil. I was 23 when I bought the 98.

The WS6? Old people owned it, probably never saw above 3000 rpm until I got my hands on it. It had 18,000 miles on it when I picked it up. Used oil, about 3/4 of quart ever 1000 to 1500 miles. After I ran 2 10lbs bottles of N20 through it at a 100 shot. It stopped has not used any oil since. It is closing in on 90,000 miles now. Has not used any oil since about 32,000 miles.

My 2024 3/4 ton had a break in period of 500 for one reason, the rear gears. I have a video of GM engineer talking about it. I just drove the truck normal for the first 500 miles. No towing, no full throttle starts. Same thing for the Malibu, we purchased that new as well.
 
Al, often stated but this is not generally true. Machining quality and tolerances have been tightly held and scrutinized in production since The Ford Model A. There have been gains in Materials science and specialized alloys and casting.

I would actually say the reverse now applies to most commodity passenger car engines with a Net Build strategy using non selected/ or assembler matched parts in critical positions (think Piston-to-bore). Only incoming material inspection of tolerances is employed.
The No fire wet spin up test booth will catch major mismatchs, errors and damaged parts to a fair degree.

Not everything is assembled with care and attention like a Nissan Godzilla turbo 3.8 V6 or a Corvette Z-06 LT6 DOHC 5.5 liter

Break it in the way you wish. Most of the time it's the luck of the draw. Moly rings and a medium-fine hone make it easy.

- Arco
Likely true down to individual parts - but you can't touch these 3 axis and 4 axis machines (Skippy chime in) with what we had decades ago - especially the short block where all dimensions need to work in concert - In fact accurate/concentric enough to use thinner lubes by far ...
 
I break mine in by getting frequent increases in the oil pressure without getting out of the torque band in the RPMs. So for example, get onto a highway onramp, manually shift it to a good gear for around 40-45mph, and do a fairly hard but steady push without downshifting from around 35mph to around 3500rpm (which might end up around 65mph). A little incline is great as well.
 
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