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Breaking in your new C7 procedure

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#1 · (Edited)
Hi everyone, I will be receiving my newly built Z51 and was wondering what you all have been doing to break the new car in properly? I have been reading different opinions like driving it like you stole it to keeping it under 4k rpm for the 1st 500 miles etc.. please advise the best procedure?
 
#3 · (Edited)
I replaced the rings in an engine myself about a year ago and looked into this quite a bit. What I found was a lot of varied opinions. The advice I settled on was running it hard in short bursts. Essentially, you want to "physically wear the new piston rings into the cylinder wall until a compatible seal between the two is achieved." This take high pressure in the cylinders, which you will not achieve keeping under xxxx rmps, as GM (and every other manufacturer) suggests. What you want to avoid, however, is the cylinder wall glazing over with overheated oil and thereby preventing that interfacing. So you don't want to run it hard for long periods.

So if it were my new car, I would nail it on the on ramps, but I wouldn't do laps at the track in the first ~500 miles. A manufacturer will never tell you to run it hard, of course, for liability reasons.

More detailed information:
New Engine Break-in Procedure

More fun reading:
http://www.mototuneusa.com/break_in_secrets.htm
 
#5 ·
I replaced the rings in an engine myself about a year ago and looked into this quite a bit. What I found was a lot of varied opinions. The advice I settled on was running it hard in short bursts. Essentially, you want to "physically wear the new piston rings into the cylinder wall until a compatible seal between the two is achieved." This take high pressure in the cylinders, which you will not achieve keeping under xxxx rmps, as GM (and every other manufacturer) suggests. What you want to avoid, however, is the cylinder wall glazing over with overheated oil and thereby preventing that interfacing. So you don't want to run it hard for long periods.

So if it were my new car, I would nail it on the on ramps, but I wouldn't do laps at the track in the first ~500 miles. A manufacturer will never tell you to run it hard, of course, for liability reasons.

More detailed information:
New Engine Break-in Procedure

More fun reading:
Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power
My opinion for what it's worth is this method. Drive it like you stole it the first few hundred miles with the right oil. Syn. thereafter.Check out the C7 oil ingestion thread by tuner boost. Makes lots of sense to me. Here it is . Enjoy the articles and your machine!

What happens now days is these engines come prefilled with M1 full synthetic, a superior oil that provides excellent protection from friction, etc. This is great for an engine that is already broken in and rings have seated properly, but it also makes the ring seating to begin with a crap shoot (GM still has excess oil consumption as the #1 warranty related service visit) as this initial period from new the rings and cylinder walls need to "wear in" to each other for a good seal. After 400-500 miles a very hard glaze sets in and then there can no longer be any further seating (we seat rings and break-in our race motors 2 runs down the track, street engines the first 100-200 miles, and rarely ever have anything but the best ring seating one could hope for).

Here is what happens when an engine is not run hard enough to create enough load on the rings to overcome the lubrication provided by the oil used:



In the old days, and still today with aviation engines that the pilots life depends on it, break in oil (a conventional mineral based) came pre-filled and it provided enough protection for the bearings and journals IF driven easy the first 500-1000 mile, yet allowed enough friction for the cross hatch hone to seat the rings properly. It was then critical to drain and fill with a good oil and then could be driven hard. If you went from the showroom to the race track with break-in oil back then you stood a good chance of spinning a bearing or worse.

Today, marketing has conditioned the buyer to get in the new car and aside from put gas in, never open the hood or consider doing any maintenance until 10k or so miles when a DIC message prompts them to do so, so this has resulted in all the re-ring jobs since 1997 when the LS1 was first introduced (that and the piston slap that was addressed with coated skirts) and GM to this day takes the stance that "consumption of 1 qt of oil per 1500 miles is considered normal" when there is no way this should occur.

So, aside from immediately draining the syn oil before driving your new car and filling with conventional to aid ring seat, driving it hard (not unsafe, not abusing it) for several full throttle accelerations, and deceleration (rings need to be loaded with both for proper BMPE to seat properly) one can then drain and change oil/filter to remove break-in debris and be confidant that the rings have seated properly and oil consumption at a minimum, and power at a maximum. The heat cycling process is also critical, during this first 50 miles stop a few times and let the engine cool and then continue.

Now we recommend driving easy the first 50 miles so the ring and pinon mesh properly and the brake pads bed as well, but other than that, there is no real critical drivetrain parts needing any break-in.

Here are some links to back this up for the skeptics (remember, the engineers don't write the owners manual):

This one probably the most informative and detailed:

http://www.tcmlink.com/visitors/carenfeed/brkin.pdf

Proper Engine Break-In - AVweb Features Article

Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power



New Engine Break-in Procedure
 
#4 ·
Personally, I break all my street engines in by driving how I'd normally drive, with the exception of holding a steady rpm, this needs to vary. I use break-in oil ( like Roush break-in oil) it has a unique way of encapsulating the foreign material that comes from the cylinder wall initial wear, suspends it, and it will flow out at the first oil change, ensuring there will be the minimal contaminants left over to cause wear.
Now then, My racing engines get assembled, and brutally beaten into submission, as they get tore down between rounds for inspection and bearing replacement.
 
#11 ·
Unfortunately, this is a logical fallacy ("appeal to authority" to be exact). Just because someone at GM (Engineer? Marketing? Lawyers? Who knows?) wrote them, does not make them right. I encourage you to do your own research and reasoning rather than blindly believe. There is plenty of evidence out there to consider, even without leaving the comfort of your computer desk.
 
#8 ·
People will have their opinions about how to get the job done right as expressed above. I can find something to agree with in almost everything posted above with some exception. To me the most important part of proper engine break-in is to me the most difficult to do. That is the avoidance of running the same engine RPM for extended periods of time. I would think that job is even more difficult to do with the auto-tranny, but certainly possible. We should not forget that the engine is not the only thing that requires a "break-in" period. There are many parts of the drive line that need to mate together and brakes require a fair amount of attention as well to avoid glazing or other irregularities. Just read the manual and heed what makes sense to you.
 
#12 ·
Run the automatics strictly with paddle shifters for the first 500 miles so you can choose the gear/RPMs to vary.
 
#9 ·
Picked my Z51 up at museum last weeks and drove home (750miles). One thing that I couldn't believe, the car knows you don't have 500 miles and the redline on the tach is 4500. Once you cross 500 mile the redline automatically jumps to 6500. I also did not hold one speed for any length of time. Also, when you start the engine cold the redline goes down and slowly rises until operating temp is reached. The technology on this car is amazing.
 
#13 ·
"...for several full throttle accelerations, and deceleration (rings need to be loaded with both for proper BMPE to seat properly)"

Which ever break in method you choose is up to you, but I know for certain from back in my drag race engine building days that the above is necessary. It is logical that you must load both sides of the piston rings and accelerationa deceleration is the only way to do so. I have done this with every new vehicle I have owned since the mid 1970s and am doing the so on my new Stingray. You can easily do this and follow the break in instructions in the owner's manual.
 
#17 · (Edited)
"...for several full throttle accelerations, and deceleration (rings need to be loaded with both for proper BMPE to seat properly)"
QUOTE]

Scott53, I'm assuming you can still do all this and keep it under the recommended 4000 RPMs that GM recommends...

I have 150 miles on it already and have "gotten on it", but kept it under the 4000 RPMs. Are you all saying that isn't necessary during the "several full throttle accelerations and decelerations"? Are the to rings already fully seated by the 150 miles?


Sent from my iPhone using Corvette Stingray Forum
 
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#18 ·
I would think the folks that designed these engines didn't call it a day at that point and head up for the house. I would imagine it is as important to them as it is us to get the most out of these 6.2's. I've never had a poor performing short lived engine by following the break in guidelines from the manufacture. I've owned over 50 new cars..
 
#19 ·
How much break-in is already done on the engine even before it is married to the chassis? I thought they ran these engines on stands to get some wear and seating on them, and then drained the oil (to get the metal filings out). Then they put the engine on the chassis a few weeks later. Also, I thought this was why it is no longer required to change the oil the first time until a regular service interval.

Am I incorrect in any or all of the aspects above?
 
#23 ·
I don't know the answer to your question, but it certainly is an interesting point. I know that during my VIP Plant Tour in Spetember 2011 I did see them crank the speed up to about 80 MPH with the rear tires on rollers near the end of the entire process. And they did not seem shy about running it up to 80 quickly if my memory is correct.
 
#22 ·
"Scott53, I'm assuming you can still do all this and keep it under the recommended 4000 RPMs that GM recommends..."

Yes, you can. I have been very careful to stay under 4000 RPMs when doing the acceleration portion. I am not smarter than a GM engineer and will not go against what the manual instructs for max break in RPMs in the first 500 miles. I must admit that the deceleration part was easier with my M6 GS than it is with my A6 Stingray. But I still think it is worth doing and I don't see how it would do any harm. And it does keep you driving at varying speeds per the insturctions in the manual. I hit 178 miles this evening. I'm not certain for how many more miles this makes sense. I'll probably keep this up to at least the 200 to 300 mile mark.
 
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#30 ·
I definitely have OCD, there is no doubt about that...
 
#31 ·
Te glen e method may break in the engine but the differential, wheel bearings and u joints need break in also with varying mph. Further the mph should not exceed 55 for the first 300 miles The method I learned 40 years ago is to accelerate up to 55 mph then coast back to 40-45, and repeat for 500 miles. Varying the gear should be performed but keep the rpms within recommendations. The acceleration and coasting aid seating of the rings.
 
#32 ·
Had the fortune to meet the C5 Chief Engineer Dave Hill, and we ended up talking about break in procedures. He said, as posted above, that varying RPM's during the first 500 miles was key, and that so were: breaking in/burnishing brakes as per the manual, easing in the the tires the first 200 miles so they were similarly broken in as the mold release was worn off, but that his biggest concern was folks not going full bore on the differential, wheel bearings and similar rear end drive components for 1,200 miles, i.e., no track use during this time period.

He also chuckled when I said to him, after my initial oil and filter change at 500 miles (which he personally liked), that I still change my oil thereafter every 3,000 miles. In his typical gentle style, he said, "it's your money, spend it the way you want, but I change mine much less frequently."
 
#33 ·
All I can say is having built race and performance engines for over 40 years, and starting as a GM tech in 1974, and also seeing so many with oil consumption issues since GM started to pre-fill the V8's w/M1, I would never baby it that first 500 miles. It is critical to seat the rings properly, and the superior protection of a full synthetic oil makes this very difficult to achieve this unless you drain and fill with a conventional oil first.





This is long, but Nissan actually breaks each engine in on the track BEFORE delivery to the customer, as does Ferrari, etc.


New Engine Break-in Procedure

Welcome to Continental Motors

Engine Break-In Procedure


The concern with other mating surfaces in the drivetrain is not valid EXCEPT for the ring and pinion and brake pads/rotors. The pads need to be bedded properly (a few brisk stops and NOT allowing the pads to remain clamped to the rotor for even bedding and heat cycling). They generally bed themselves fine. And the Ring and Pinion. These will take app 50-100 limes to "wear in" to each other and a few heat cycles, every other part will never be as true and perfect as when it leaves the factory and there is no need for breaking on any other component.

So, from a tech and engine builders view, most would rather seat the rings properly to begin with than come back for warranty claims requiring a re-ring later due to excess oil consumption.

It seems only Aircraft engines now come pre-filled with proper break-in oil that facilitates proper ring seat. And the pilots and passengers lives depend on this being done correctly.
 
#34 ·
Valid points.

Can only provide my personal and very limited experience with my brand new C5 and C6 Z06. I followed GM's break in procedures exactly, and despite many other C5's and C6's experiencing lots of severe oil consumption issues -- with more than a few going back to dealerships with owners complaining about a quart of oil needing to be added at 500 miles, 700 miles, etc., I never added, nor needed to add a quart of oil to my C5 between its 3,000 mile oil changes, nor in my C6 Z06 with its 3,000 mile oil changes.

On both, I did one additional oil/filter change, replacing the factory oil and filter at 500 miles to get out all the minute metal particles from initial engine break in. Lucky? Perhaps. Will I do exactly the same thing on my '15 Z06? Absolutely -- unless GM changes the break in procedures for the LT4.
 
#35 ·
You were a luck one for sure, and plenty of others doing the same have had no issues so thats proof your not guranteed to use oil....but the hard break-in is assurance the rings will seat correctly.

I also wanted to point out that it was mentioned U-joints and wheel bearings, etc would need break-in. The C7 has no u-joints in any part of the drivetrain and the sealed wheel bearings are a cartridge type assy and will never be more perfect than when new, so that does not apply either.

:thumbsup:
 
#38 ·
Mine will get driven back to Florida from Bowling Green via the TN/NC/GA mountains. I'm pretty sure everything will be bedded, run in and seated quite nicely before the first oil change :)
 
#41 · (Edited)
VERY interesting post! In reality all we can discuss about the Corvette (or any car!) seems to be quite peanuts comparing to the break in process as this one seals definitely the way your engine will run for all his life!
Naturally when you go to take your brand new Corvette you're very happy, very excited and there are plenty things you want to discover, etc. and I'm sure that "cooling" this enjoyment because you have to take immediately care of a binding break in process is not the best thing you could hope :(

The important question now is. WHO HERE HAVE DRAINED THE ORIGINAL GM OIL BEFORE TO START THE BREAK IN to use mineral break in oil?
After reading all the linked articles I'm definitely convicted that the explained process is the better way to assure the best possible break in process, so using immediately the OEM synthetic oil can ruin completely the explained process as this oil is too slippery and will cause definitive glaze (read articles) lower output and too much oil consumption risks.

Second important question is : have you asked for this immediate oil change to your dealer or have you organized that for yourself to avoid any problem with him if there will be one time a warranty claim regarding the engine ?

Third question: Following the break in process with mineral break in oil, this one + the oil filter would have been changed by the SAME oil after about to 150/200 miles to eliminate the metal particles present after the first running miles. The synthetic oil would have to be used only after around to 1500 miles. Anybody did that or plans to do ?

I don't know for yourself but even if this break in process should get you anxious vs the OEM process, there are a lot of technical facts that cannot be ignored (for example the pistons and rings look/condition differences after OEM and upgraded break in process are incredible). See here in the middle of the page,
http://www.mototuneusa.com/break_in_secrets.htm
beside that this Website have plenty of things to read, not only this page.

P.S.I have two defects: English is not my native language and I'm a newbie here, so please be tolerant :eek:
 
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