Popular Mechanics - How to Break In a New Car

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34,194
Location
South Jersey
http://www.popularmechanics.com/cars/how-to/saturday-mechanic-blog/how-to-break-in-a-new-car
Quote:
Engine Cylinder Walls Piston rings don’t rely on their spring tension to seal against the cylinder bores. Instead, combustion gases work their way between the rings and the piston and force the rings outward. During the first few minutes of engine operation, it’s important that the throttle be opened pretty far at lower rpms to provide this high pressure. Otherwise, the rings won’t burnish the cylinder walls properly, and the engine will have high volumes of blow-by—which means excessive oil consumption and shortened engine life. If you’ve ever seen the car jockeys who drive new cars off the end of the production line into the storage lot, or the transporter drivers zipping up and down the car-hauler ramps, you’ll realize that this all-important step has been performed for you many times. If you’re installing a new engine, simply give it a few seconds of wide-open throttle in a high gear. For the first thousand miles, avoid constant speeds and throttle settings. If you commute in normal stop-and-go traffic, you’ll be fine. I advise against cruise-controlled sojourns across Nebraska.
 
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5,926
Location
Waterloo, ON
Just when you thought you had heard it all... "I customarily change the oil in a new engine after about 20 miles", He says this in one paragraph: The conventionally wisedom says that synthetic oil is too slippery and won’t let the microscopic high points properly lap themselves in, delaying the break-in process. I say rubbish. Many modern cars, notably such high-performance marques as Porsche, Ferrari and Corvette, are factory-filled with synthetics. You can bet that somebody has determined that the break-in process will proceed normally with synthetic in the sump of these ultra-high-performance engines. And in the next paragraph: Nonetheless, I do prefer to use a mineral oil for break-in. crzy
 
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Messages
2,806
Location
Michigan
holy mother of new car engines, I once bought a honda accord with 2.x miles on it, stealership drove it another 5 miles for pre-deliv inspection. I took it out to the hwy (yes hwy), not in NE but close on I-29 and drove it at final drive from 50 to 70 mph for 40 miles, man that was the longest 40 miles I ever drove, nearly got hit many times when I was engine braking. Guess what, I sold that a year after. Since then I am a fan of drive it like you stole it gang. Call me crazy but worked fine for till now. Hey it works for motorbikes so it works for car engine :-)
Originally Posted By: buster
http://www.popularmechanics.com/cars/how-to/saturday-mechanic-blog/how-to-break-in-a-new-car
Quote:
Engine Cylinder Walls Piston rings don’t rely on their spring tension to seal against the cylinder bores. Instead, combustion gases work their way between the rings and the piston and force the rings outward. During the first few minutes of engine operation, it’s important that the throttle be opened pretty far at lower rpms to provide this high pressure. Otherwise, the rings won’t burnish the cylinder walls properly, and the engine will have high volumes of blow-by—which means excessive oil consumption and shortened engine life. If you’ve ever seen the car jockeys who drive new cars off the end of the production line into the storage lot, or the transporter drivers zipping up and down the car-hauler ramps, you’ll realize that this all-important step has been performed for you many times. If you’re installing a new engine, simply give it a few seconds of wide-open throttle in a high gear. For the first thousand miles, avoid constant speeds and throttle settings. If you commute in normal stop-and-go traffic, you’ll be fine. I advise against cruise-controlled sojourns across Nebraska.
 
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1,502
Location
Ohio
Only thing I did different was varying speed during the break-in on the Honda. Changed the factory fill at 10,040 miles when the MM indicated. I maybe had to add 1/2 quart during that first 10,000 miles, but since then it's never used any noticeable amount. Just rolled over 107,800 miles.
 
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4,942
Location
Kansas
While I have read some really off-the-wall car articles in magazines or on the web, I don't think this one is one of them. At least it's not too bad. As far as the spring tension on the piston rings, the compression DOES push out the piston ring against the cylinder wall. It always has. It's just that now some of the manufacturers are putting a low tension compression ring (instead of a piston ring that had more tension) on the piston to eek out just a little bit more horsepower and higher gas mileage. One of the earlier engines do do this was the Mustang with the 302 a couple of decades ago. Usually, engines with low-tension rings will use more oil than engines with regular rings, at least when they get some high miles on them. IMO, if an engine gets overhauled, replace the low-tension rings with regular rings. As far as babying an engine or hitting redline during an engine break-in, that all depends on the piston rings. The old cast iron piston rings or even the chrome rings took a little breaking in. The only cast iron ring usually took a few thousand miles to be broke in. 60 years ago, mechanics would start a freshly overhauled car engine and have a garden hose in the top of the radiator because the cast iron rings and poured babbit bearings would make the car overheat during the first startup. A modern moly ring is about broke in a few minutes after the engine has been started. As far as changing the oil in 20 miles, that's really too soon. But it also depends on an engine that was assembled in a manufacturer's clean room or somebody "overhauling" an engine in their dusty garage. An engine assembled in a clean environment with close tolerances and modern roller lifters can easily go 3K on the first startup before an oil change is needed. (Still too many miles for me, but they CAN go that many miles) I'm guessing the author puts dino oil in his car during the his break-in just because synthetic is too costly to dump for just 20 miles of use. Just my $.02 worth.
 
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1,321
Location
WV
I have changed the oil in new cars at 500 miles and another at 1000 miles. I put the drained oil in the sun and you can see all kinds of metal, brass, bronze, steel etc. I don't think you have to change that early but I would not want all that metal circulating for 10k miles.
 

ls1mike

$50 Site Donor 2021
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6,788
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In the Garage...
Break it in how you are going to use it. The Trans Am has seen full throttle since day 1 at least once a day when being used, doesn't burn oil has never broke unless you count clutches and rear ends at the track. smile Drive it like you stole it...Has always worked for me.
 
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28,123
Location
Regina, Saskatchewan, Canada
Originally Posted By: Bluestream
Nonetheless, I do prefer to use a mineral oil for break-in. crzy
It's not completely nuts. After all, if one is doing a short first OCI or two, a conventional would be more cost effective.
 
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5,133
Location
chicago, Illinois
If your car is a typical mass produced model from any major manufacturer change the oil when the owner's manual tells you to. There is NO need to change oil out at just 3000 miles on most any mass market model today. Usually the interval is at least 5000 miles and often times 7500 to 10000 miles.
 
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19,528
Location
Lake Forest, CA
Honda is very adamant about leaving FF for full MM, but some owners still change FF out early and the engine didn't suffer any negative effect. Personally I left FF in all my cars to full MM, never changed it out early and all engines are good for up to 360+k miles in the LS400. I just drive it like normal during break-in, easy the first 2-3 miles after cold start then redline if needed after that.
 
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1,841
Location
Southwest
Ford F-150 says variable speeds, avoid full throttle acceleration. I forget how long this was supposed to be. That's not much of a limitation. Old Nissan Pickup said basically what this article did: Brisk acceleration followed by fairly abrupt letting up on the accelerator. Something about sucking oil up into the cylinder heads. Car went 260K with the engine never missing a beat before getting totaled. I will say that on the Nissan I could actually feel it running a bit looser towards the end of the trip, a 280 miles trip from The Big City. Of course, if you are really concerned about break-in, the only thing to do is to buy a rental car. That's the way to make sure your car has had plenty of this "variable" driving they talk about.
 
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Messages
1,051
Location
New Zealand
The only things I would do to a new car specifically is (a) avoid short trips. Try to minimise the time below full operating temperature so that the rings bed with the bores in the shape they will normally be in. And (b) avoid high revs where ring lubrication might be less than ideal at the high points. Other than that I think normal driving is just fine.
 
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19,686
Location
Sunny Florida
Originally Posted By: ls1mike
Break it in how you are going to use it. The Trans Am has seen full throttle since day 1 at least once a day when being used, doesn't burn oil has never broke unless you count clutches and rear ends at the track. smile Drive it like you stole it...Has always worked for me.
Likewise. I own a 'known' oil burner yet mine uses nary a drop, even at road course track days with oil temps of 300 degrees. My factory manual says full throttle is beneficial to engine break in. Use upper gears and get on it, low tension rings need combustion pressure to form a good seal...
 
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11,660
Location
NorthEast
Quote:
Honda is very adamant about leaving FF for full MM, but some owners still change FF out early and the engine didn't suffer any negative effect.
I do not believe you have the data to accurately assess this. Only recently Honda started making that recommendation. All the current 200-300K Hondas on the road did not have that recommendation from the factory.
 
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2,302
Location
ohio
I don't understand why this is an annual issue. Follow the recommendations in the owners manual.
 
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5,926
Location
Waterloo, ON
Originally Posted By: Garak
Originally Posted By: Bluestream
Nonetheless, I do prefer to use a mineral oil for break-in. crzy
It's not completely nuts. After all, if one is doing a short first OCI or two, a conventional would be more cost effective.
My point was to show his total contradiction on is statements, not to argue using conventional would be more cost effective. BTW, he never mentioned cost effectiveness as the reason he breaks in with conventional oil
 

buster

Thread starter
Messages
34,194
Location
South Jersey
Originally Posted By: SteveSRT8
Originally Posted By: ls1mike
Break it in how you are going to use it. The Trans Am has seen full throttle since day 1 at least once a day when being used, doesn't burn oil has never broke unless you count clutches and rear ends at the track. smile Drive it like you stole it...Has always worked for me.
Likewise. I own a 'known' oil burner yet mine uses nary a drop, even at road course track days with oil temps of 300 degrees. My factory manual says full throttle is beneficial to engine break in. Use upper gears and get on it, low tension rings need combustion pressure to form a good seal...
I agree. I've said many times before that a few full throttle blasts in a high gear/low rpm works great. All the cars I've owned that were broken-in this way never consumed a drop of oil. The two that were babied did. Possibly just the nature of the engine, but this article swayed me over for good. The writer agrees that WOT/low rpm is best. *fwiw, a GM engineer that worked on the LS1 engine was a member here years ago and he also said this is the ideal way.
 
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