[misterjaayy]

Originally Posted by Oil Man

Only 10?

If you really want to stir the pot, ask in a month or two how no-lift shift works...

This kills me. He didn’t see an answer he liked in the probably dozen threads already discussing this issue in depth so he looks for the end all-answer by asking the exact same question with the exact same answers?

[PersonX51]

heh changed the "break-in" oil at 500 miles. put Schaeffer's 9000 series 5W30 in it. ( I normally change oil every 4 to 5000 miles ) at 1500 miles took it to the drag strip put a dozen hard passes on it... oh and in between then and now I put a few 160+ mph runs on it... It makes no funny noises at idle ( never did ) and runs like a top... don't be afraid of it its not a expensive flower vase... its a car... drive the damn thing!!

[dpevans]

I did what the owners manual said. Nothing over 4k, no hard downshifting, no constant RPMs for long periods of time. No issues. AND DO CHANGE the rear end fluid.

[BigShow1960]

https://my.chevrolet.com/content/dam...tion-guide.pdf

[Elite Engineering]

Here is what GM sends with every replacement engine, LS, LT, etc. and is absolutely the best most effective way. We just go to 5k RPM instead of 4500. And no, NO engines come already broke in from the factory.





The reason you the consumer does not see this is the liability involved with instructing a "un trained" consumer to follow this.


Think about the owners manual instructions. First, first oil change at 3000 miles? After a high number of catastrophic engine failures GM now released bulletins to change factory fill oil on the Z06 at 500 miles. These failures were caused by several factors all related to leaving the factory fill oil that is full of damaging abrasive compounds in for that long. The ONLY reason Automakers tell people they can go 3-5k miles before the first oil change is pure marketing to appeal to today's buyer that does not want to be troubled with having to come in for service so soon. This has nothing to do with whats best for the engine longevity.


Now lets look at one of the most important aspects of the break-in process as far as the engine is concerned. The crank and cam journals are polished to perfection so nothing to wear in there. Bearings have very little shedding of metal as they are also close to perfect when installed. Rocker arms? Nope, needle bearing pivots and only the end that rides on the valve stem ends does any "break in". That as well is very minor and requires no "easy" driving, in fact the best is varying RPM's from idle to 5k for best results. Rare to ever see failures there. Pushrods and lifters? Again, other than very minor wear in of the cam lobes, also best done at higher RPM's. Now, the most critical....the piston rings. The rings are your only barrier between the combustion chamber and the crankcase. All engines have some blow-by, but the goal is the least possible. In order to do this, the rings must wear in, or abrade to the shape of the cylinder walls. And in doing so they generate a large amount of iron filings. And how this is done is with the abrasive cross hatch hone pattern we cut into the cylinder walls before assembly. Here are some illustrations to show what happens when this goes as planned:





BUT, this must occur evenly, and in the first few hundred miles or this is the result that causes oil consumption and excessive blow-by issues:





Why? In the "old days" engines came factory filled with a low viscosity "break-in" oil. This oil was just enough protection that if driven easy, would protect the bearings and other surfaces while still allowing penetration of the protective layer so the rings could seat quickly and correctly. Oil was then changed by 500 miles and then a good oil filled and you could drive hard. Today, these engines come filled with a syn blend that is far too protective so it takes some "force" to penetrate that lubrication barrier and allow the "wear in" of the rings and cylinder walls for a good seal. So, if you follow the owners manual, you probably have a 50/50 chance the rings will seat well enough to not use excessive oil, but 50% that they will not. So if they do not fully seat, and seat evenly in the first few hundred miles, that short window ends when a hard glaze sets onto the cylinder walls and covers the cross-hatch so little to no further seating can occur. When you follow GM's instructions for Techs, you find the engine braking will put even forces as occurred during acceleration and the best possible even wear-n occurs resulting in the best seal possible. No engine oil consumption, minimal blow-by, and more power due to the better seal.


Valve springs need several heat cycles to break them in right. Heat up and cool down.


What is in the crankcase when your new car leaves the factory? Well, the silicates and other foaming causing compounds present from assy and machining coat the surfaces and contaminate the oil. Also the different metal filings shed from ring seating and other minor wear-in. Assembly debris suck as brush bristles, shed abrasives, and other metal that comes loose when run that adhered to the surfaces. Casting flash being common. Here is an example of a filter:



Above shows stainless steel brush britles that were shed during assy. NOT good to circulate in the oil. The filter trapped it, but it most likely did some wear/damage before this.



This shot shows shiny silver (aluminum) and gold (brass/copper) metal that comes from casting flash and some bearing material as the particles have been causing premature wear (this was 500 mile first change).


What about the trans and rear diff and brakes? Brakes are bedded with a few hard stops and never keeping pedal depressed so the rotos can heat cycle evenly. Nothing in the trans has to wear in, all is as it should be. Some minor gear meshing. Rear diff 50 miles.


So, reading owners manuals today always makes me chuckle at how they are written. Minimal accurate advice for getting the most trouble free life from your new vehicle, and most to shield the company from liability, and of course reinforcing marketing strategy.


Hope this helps, but bottom line is ONLY do as you feel comfortable doing. You own the vehicle and you have to treat it as you choose.

[Wheel Team 6]

My car arrived with 3 miles. I took possession driving it on short trips stopping and going shutting it down letting it cool then driving again. My stealership scheduled me to come in at 1000 miles for the break in oil change. Did that then drove the car to 5000 miles then did the first oil change. Tech cut open the filter didn't see anything abnormal. Just hit 6000 miles yesterday car feels great. Taking it to the track next week. Hopefully all stays good and it performs well.

[Blazin383]

Yep, and if you bought yours new off the lot... that 50 or 75 miles on the odometer are from 10 people who test drove it before you bought it and every one of them put their foot to the floor at some point during the test drive, and undoubtedly well before the oil temp was up to operating temp etc! And by the way, the salesman riding along encouraged it!

[Donner]

Hello,

You are going to get a lot of advice for a question like baby it, or romp it in here; It has been my experience that the thrash it and trash is crowd don't care about the end game. Few of those people are intending to keep their wheels for a lifetime or better. Anyone with enough coins to throw turbos, superchargers, and squeeze bottles (Nitrous Oxide) on their whips rarely keep them long term either. For proof of such claims, look at the number of cars with mods on them (that are relatively new vehicles) and are now for sale compared to those that are in stock form. The manufacturer says what they do for good reason. Hop up shops sell parts. The more folks abuse things, the more stuff they sell. Simple math. Manufactures would like to avoid costly repairs so they are in favor of taking better care of the engine and drive lines until they are properly broken in. Again, simple math.

Do as you will; it won't affect my world.

Kindest,

Donner

[Bluecyclone]

^As the "World Turns" can continue, I do my R&D and am better for it. I broke-in my motor and did a quick oil change. My GT gets 22 mpg at 70 mph to 75 or so. I road warrior my pony thru S curves & Chicanes and have very little blow by or consumption.
See you in the Twisty's!

[enzia35]

I followed the manual procedures.