BoBcanada

Guys did you brake in your cars ? How should i drive it first 1500kms? any suggestions?

Picking it up tomorow!

DFW01E55

That depends, are you buying or leasing?

That's the way a high ranking Mercedes employee (not dealer) answered the question when I asked.

BoBcanada

lease for 3 years. But i want it to run properly and as fast as others

Beowulf

Some interesting observations from viper, posted in another engine break-in thread:

"Drive the car for what it is - a high performance sedan. The first 20 miles determine the longevity of your engine. If you drive it too easy, the piston rings don't get seated properly and you risk contamination of your engine oil from that point on. The idea that you must baby the engine for the first 1000 miles was back in the old days when part tolerances were very sloppy.

My information comes from experience. I work in software development on engine test systems for one of the Big 3 domestic manufacturers. I know how engines were built and tested in the early 80's and how the assembly and test methodology has changed over the years. Cold and hot testing of engines was in its infancy back then. Today the quality of engines that are produced is light years ahead in durability and efficiency.

Run the engine hard during break-in just don't abuse it. Nobody said said you should approach redline. If you baby the engine too much you won't expand the piston rings enough and you end up leaving a thin film of oil on the cylinder walls. This film will oxidize with the high combustion temperatures and will induce glazing of the cylinder walls thus leading to high oil consumption. Glazing can only be corrected by rehoning the cylinder walls at considerable expense and inconvenience to you. You certainly don't want to have this done to a brand new vehicle."

Omegaonne

check the manual. It says not to go over 85 mph for the first 1000 miles and not to exceed ? rpms. Don't drive it at a consist speed. Punch it once in a while when you see a Bimmer who thinks the M5 is a better car. Flash you emergency lights when u see another benz as a sign of respect. Ok the last two I made up. Sorry

RossN

This was covered last month under the thread titled, "The "Lance Wolrab" Break-In Procedure - Since So Many Have Asked " graciously dug up by member Marcus Frost. Click here for Thread.

Here is an excerpt of the post covering actual break-in procedure.

"I have been using this procedure for many years (at least 18 years). I both agree and disagree with the link you posted. I'll explain why after you see my procedure.

I have a standard break in procedure that I use, it takes about an hour if you are diligent, and when you are done, break in is complete. The biggest point of grief with a new engine is the unrelieved stresses in the pistons. You want to heat and cool them in a predictable way with an incrementally increasing thermal load. I usually start at 20% throttle and go in 10 or 15% increments until I get full throttle. Bursts should be 15 to 30 seconds, followed by 5 minutes part throttle cruise to let the pistons cool and resize themselves. You can figure out that 30 seconds in top gear at full throttle will have you going pretty fast down the road, so you need a clear stretch to do this, but I have never had a problem with leak down or bad piston fit using this technique. That crap about "XXX" miles is just so the average driver doesn't blow things up.

Also, I assemble the cylinders dry, but turn the engine over for about 15 seconds with no fuel or ignition before my initial start up, then I run it up to about 25% of redline as soon as it catches for 30 seconds or so. Once I have my initial 30 seconds and no gushing leaks, I take it out for a drive right away. I want to put pressure on the rings and valves to get them to seat well and that can't be done without a load, so off we go down the road for about 5 minutes, then return to the shop to check for oil or coolant leaks. If all is OK, back out on the road for final break in.

OK, that's what I have recommended. I disagree with Motoman because he is ignoring the whole issue of grain structure in the pistons. If you are using used pistons, then there is no need for any kind of loading tactics like these, just a few full throttle runs at soon as the oil is up to temperature to seat the rings and you are done. Cast pistons have not aligned their grain structure after casting, and forged pistons have unrelieved stresses from the forging process. Both require heating and cooling cycles to allow the grains the opportunity to align themselves under thermal load. It isn't possible to do this in the manufacturing process because pistons are not heated evenly in service. This process is no different than heat cycling your tires, a well known science among racers. I completely agree with Motoman's assessment of the manufacturer's recommendations. They are crap. I also completely agree with getting a load on the engine as soon as you can. I didn't notice any admonishments about allowing a new engine to idle, but I NEVER allow a fresh engine to idle, it is the kiss of death IMO.

Ken, in your situation, you have little or no control over how the engine was initially fired, and BMW being reasonably intelligent and diligent have already used an initial firing procedure designed to seat the valves and rings quickly. Just take it out and drive it, put a load on it, and be happy with it.

Lance
'93 TT 6 speed Coupe"

Hope this helps, err... adds to the confusion (debate).

RossN

Here is the Motoman site referenced in the above post, http://www.mototuneusa.com/

And here is the "Break-In Secrets" article Motoman has become famous for. Pull up a chair Ladies and Gentlemen, this guys website takes hours to fully digest, but it is interesting through and through. Lots and lots of supportive data in here to sway the most reluctant mind, http://www.mototuneusa.com/break_in_secrets.htm

Good luck in making your choice Bob! Heehee, basically you can't go wrong with either choice, or can you???? :p

Beowulf

Yep, recall the Lance Wolrab method - my concern is local traffic conditions and amount of road available that would allow this procedure to be applied. Wonder if anyone's tried this on a Mustang dyno, where you can simulate real world frictional loads?