Break In Speeds

[Mason57]

I have traded my 04 SSR for Tony Stewart ( Brickyard 400) 06 SSR. I'm going to IA. to get it. It has 50 miles on it now. I will be driving about 1300 miles to my home. All Interstate driving. Does anyone know at what speeds I should break it in for the first 1300 miles? Speeds and for how long at that speed. I thank anyone for any help on this. Mason

[KySSR]

Where is JimGnitecki when you need him? He knows about everything that has to do with the SSR.

[2005SSR6Speed]

I just drive it like its a rental, there is no need to worry about breakin. The only thing I ever do is change the oil at 1000 and then every 3000 there after. I have never had any problems with oil consumption or any other problems associated with breaking in the engine. My 2005 was broken in hard, the way I drive it all the time. My next engine will be broken in on the drag strip.

[JimGnitecki]

I sent Mason a pm but also wanted to post this so that in the future new owners can be directed to do a search on "break-in" and I don't have to write a brand new one each time!

Mason: I had to edit my private message, as that medium limits the number of characters, so the version below has much more detail and explanation.

Interstate driving is the worst possible break-in environment, so I'm glad you asked.

With any engine, the keys to a good break-in that results in a strong engine are:

- Most of the critical break-in is done in the first 200 to 300 miles. It's all over by 500 miles or so if you do it right. The factories sometimes say 1000 miles, but that's because they know most people will not do the PROPER break-in because it's a pain or not possible in their traffic environment, so an "improper" one takes longer.

- Do NOT cruise for long periods of time at steady speed. Vary the speed, accelerate and decelerate very frequently.

- Raise the rpm limit that you run the engine to a bit at a time. Do NOT run high rpm early in the break-in, no matter how tempting

- Vary the LOAD by accelerating and decelerating, but never apply a heavy or prolonged (more than few seconds) load until after break-in is complete.

A practical and very effective break-in that will work on the interstate, if you have the patience for it, would be:

For first 100 miles on odometer:
Coast DOWN 10 mph from cruising speed
Accelerate at 1/4 throttle to 10 mph OVER cruising speed
(i.e. you are accelerating up total of 20 mph)
Coast back to cruising speed
Cruise for 2 minutes
Repeat

For the 100 to 200 miles period on odometer:
Coast DOWN 10 mph from cruising speed
Accelerate at 1/2 throttle to 10 mph OVER cruising speed
(i.e. you are accelerating up total of 20 mph)
Coast back to cruising speed
Cruise for 2 minutes
Repeat
(Note: if the automatic kicks down, that's ok PROVIDED you don't let the rpm by the end of the acceleration period exceed about 3500 rpm. That's still about 80 mph in 3rd gear)

For the 200 to 300 miles period on odometer:
Coast DOWN 10 mph from cruising speed
Accelerate at 2/3 throttle to 10 mph OVER cruising speed
(i.e. you are accelerating up total of 20 mph)
Coast back to cruising speed
Cruise for 2 minutes
Repeat
(Note: if the automatic kicks down, that's ok PROVIDED you don't let the rpm by the end of the acceleration period exceed about 3500 rpm. That's still about 80 mph in 3rd gear)

For 300 to 500 miles on odometer:
Drive "normally", but try to NOT cruise at steady speeds for miles and miles. Pass cars, slow down and speed up, just don't "sit" at one rpm and load for long periods. Keep maximum rpm under about 4000.

For 500 miles to 1000 miles on odometer:
Drive as you like, BUT keep maximum rpm under about 4500.

After 1000 miles: No special restrictions.

If you run into traffic, you obviosuly cannot safely do this, but then if you just try to do your share of passing and lane changing, etc., you can at least prevent the absolute worst scenario: steady state cruising at one rpm for long periods. That results in a really lousy engine break-in.

If you have a 6-speed instead of an automatic, do not use that stupid 6th gear for the first 1000 miles. It runs your engine at WAY too low an rpm for a good break-in. In fact, it runs your engine at way too low an rpm period! A high rpm engine like the LS2 in an SSR should not be run at less than about 1800 rpm on the highway (I mean after break-in even). These low highway rpms we are seeing are the result of a whole generation of engineers being beat up to get a good EPA fuel mileage rating, even if it is bad for the engine.

During the 0 to 1000 miles on odometer, check the engine oil level at each gas stop. It should either be using none or very, very little oil.

Also watch the engine coolant temperature gauge. It should not be allowed to exceed about 235 ever during the break-in period. SSRs run hot, so a "normal" reading under cruise conditions is 190 to 210. Accleration or stop and go can raise it temporarily to as much as 235. Above that is abnormal. Abnormal is especially bad for an engine that is not yet broken in, as it is much easier to do damage to it.

Jim G

[Boosted]

here is the rule I always followed.

What's The Best Way To Break-In A New Engine ??
The Short Answer: Run it Hard !

Why ??
Nowadays, the piston ring seal is really what the break in process is all about. Contrary to popular belief, piston rings don't seal the combustion pressure by spring tension. Ring tension is necessary only to "scrape" the oil to prevent it from entering the combustion chamber.

If you think about it, the ring exerts maybe 5-10 lbs of spring tension against the cylinder wall ...
How can such a small amount of spring tension seal against thousands of
PSI (Pounds Per Square Inch) of combustion pressure ??
Of course it can't.

How Do Rings Seal Against Tremendous Combustion Pressure ??

From the actual gas pressure itself !! It passes over the top of the ring, and gets behind it to force it outward against the cylinder wall. The problem is that new rings are far from perfect and they must be worn in quite a bit in order to completely seal all the way around the bore. If the gas pressure is strong enough during the engine's first miles of operation (open that throttle !!!), then the entire ring will wear into
the cylinder surface, to seal the combustion pressure as well as possible.


The Problem With "Easy Break In" ...
The honed crosshatch pattern in the cylinder bore acts like a file to allow the rings to wear. The rings quickly wear down the "peaks" of this roughness, regardless of how hard the engine is run.

There's a very small window of opportunity to get the rings to seal really well ... the first 20 miles !!

If the rings aren't forced against the walls soon enough, they'll use up the roughness before they fully seat. Once that happens there is no solution but to re hone the cylinders, install new rings and start over again.

An additional factor that you may not have realized, is that the person at the dealership probably blasted your brand new toy pretty hard on the "test run". So, without realizing it, that adrenaline crazed set - up mechanic actually did you a huge favor !

[2005SSR6Speed]

Boosted - Well put.

[Mason57]

This truck has 50 miles on it and it was at the Brickyard track. So I am sure they put it though it's paces. I still like Jim G's advice. I want to thank everyone for there help. Mason

[BlastfromPast]

This age old debate has been running on for decades! For my money (and experience), the kinder, gentler approach to break-in (such as Jim G's recommendations) have proven to be well worth the effort in the long haul.

Let the debate continue . . . .

Blast