Best Break-in Procedure
 

I tried searching and couldn't find a topic on this (I'm also lazy though).

I noticed people were discussing the break-in procedure in other topics so I figured it would be easier to have the holy war fought in one place.

What's everyone's opinion on the proper break-in procedure?

I've never had a new car before, so I'd like to see some good arguments with preferably a lot of reasoning, citations, and good references on what is the best way.
:popcorn:

There is no need for brake ins any more. Machining and manufacturing tolerances have gotten better lately and it eliminated the need for wearins. Eg my gfs yarris didn't need one. Her sisters corolla didn't need one either. Wear in is a period when engine components experience intentional wear to create proper surfaces for adequate lubrication. Developments in manufacturing techniques as well as better more controlled oils mean that the surfaces are already made at the optimum levels and roughnesses to create adequate separation under hd and ehd lubrication regimes
My only other citation is my degree that I completed and the fact that involved extensive tribology and component and material manufacturing context
Traditionally you would use a slightly thicker oil and change it at high intervals (like every 1000km) to a slightly thinner one until you get to the proper thickness

Interesting! What about ring seating?

Break her in hard.

^This. I can never hold back for 1K miles (or whatever the generally accepted break-in mileage) before driving hard in a new car. That would be pure torture. Of course, I'm not stupid either so I don't go redlining everywhere. But I guess if I had a car whose engine was prone to explode if not treated properly, then I might think twice about breaking it in hard. We'll just have to see how many failures we get in the first batch of FTs.

So, would this be ideal?

1) Turn on car (yes I'm going to be that specific)
2) Drive nicely until temperature show it is at operating temps
3) Floor it from 1st, shifting up until speed limit permits ;)
4) Brake, or downshift to engine brake?

Yeah sounds about right. I always made sure to drive moderately to warm up the car, then I go for some "spirited" driving. I also only downshift/heel-toe when there's a turn involved. Approaching red lights and stop signs, I just brake like normal. I drove this way during "break-in" and I still drive this way. Car has been going strong for 6 years.

Pretty much the same thing all around. Drive the car nicely until she is warm. After that is when you can set all thrusters go. As for braking myself, I recommend not slamming on the brakes and you should be fine. :)

First cranks of the engine are very important, and there is a certain tech to breaking in fresh engines, but since 99% of brand new cars already have been ran for a Lil bit and it's not the first start-up by the time it's you, there isn't really a need for the entire break in, granted if it's a manual, I'd give the clutch 500 mi break in, and like he said on the pistons rings, 1000 mi.

the rings are seated within the first 50 miles. but definitely be easy on the clutch for the first 500.

the best way to seat rings is to let the vehicle warm up, drive it gently. once up to operating temp, get onto a highway, get into 3rd gear. got WOT, from say 3000rpms to 6000 (just an example, obviously use your judgement). you don't want to lug the engine at low rpms and high throttle, and don't go all the way to redline. snap the throttle shut and let it engine brake back down to 3000rpms. repeat 10 times or so. change oil. done.

This is what I was referring to on brand new engine, or freshly rebuilt

I mentioned the mototune method on another thread. I've utilized that procedure on all the bikes I've own/ed which is probably more crucial than a car since they use "wet sump" clutches (oil lubricates both engine and clutch). I've used it on my Tacoma when I brought it new. The SS bikes have higher reving engines on a lightweight frame so you'll notice any amount of increase power or loss of. I've ran them on the track numerious times; 100 degree track temps, 20-30 min sessions pinning the gears from 50-150mph for the whole day. That puts a lot of stress on an engine so it's key to break it in properly.

Blocks today are honed so fine but the goal is let the rings seat but also flush out as much minute debris as possible.

I use the Shell Rotella b/c it's cheap, doesn't have molybdenum and friction modifiers (Energy Conservation). <-this may only apply to bikes since it slips the clutch more.

Here is what I do:
-start the engine
-let it warm up
-load 1st and 2nd gear (repeat several times for about 20 miles)
-drain the oil (this is where I've seen the oil really dark and tiny metal specs)
-repeat to load the engine till you get to 50 miles
-drain the oil
-maintain loading the engine till 150 miles
-drain the oil

Sometimes I'm adament and replace it again at 300 miles but that can be subjectively up to you.

http://www.mototuneusa.com/break_in_secrets.htm

Yeah I was reading the Moto Tune page at work from you. Thought I'd make a new topic to get more opinions instead of reply in the other topic.

What about the differential? I think I'd drain that really soon too... maybe first 50 miles, then 500. I've never had a car with a diff.

i also run Rotella, in my MR2. it's diesel oil, so i know it can handle a turbo just fine, as well as solid lifters/tappets. seems to like it.

definitely not a bad idea if you plan on keeping the car for a couple hundred thousand miles.