[Shakes]

Originally Posted by m6pwr

OP: break-in "theories" covered here -

http://f30.bimmerpost.com/forums/sho...d.php?t=919690

My suggestion: follow the basic limits prescribed by BMW in the Owner's Manual.

thanks a lot

[munch520]

Originally Posted by m6pwr

OP: break-in "theories" covered here -

http://f30.bimmerpost.com/forums/sho...d.php?t=919690

My suggestion: follow the basic limits prescribed by BMW in the Owner's Manual.

Agree.

This is just me, but I'll take it out (once warm) with about 10-15 miles on it and do a 3rd or 4th gear pull (whatever I have room for) and let the gear slow the car down, no braking. This is an old sportbike thing I subscribe too, basically gets the rings to wear against the cylinder walls for a nice snug fit.

I think this is touched on in some break in threads as well. But yeah, I plan to baby mine for the most part for the first 1200mi.

Saw a guy last week at the dealership cold start a 335i and immediately start revving it to redline. No amount of break-in period will help that car...

[Shakes]

Originally Posted by munch520

Agree.

This is just me, but I'll take it out (once warm) with about 10-15 miles on it and do a 3rd or 4th gear pull (whatever I have room for) and let the gear slow the car down, no braking. This is an old sportbike thing I subscribe too, basically gets the rings to wear against the cylinder walls for a nice snug fit.

I think this is touched on in some break in threads as well. But yeah, I plan to baby mine for the most part for the first 1200mi.

Saw a guy last week at the dealership cold start a 335i and immediately start revving it to redline. No amount of break-in period will help that car...

i read in the manual once you start you take off right away gradually, instead of letting it warm up. is that ok to do??

[Ali Shiralian]

2000km, RPM under 4500. Having said that I revved it too high a few times before that. It's just too much fun to resist

[m6pwr]

Originally Posted by Shakes

i read in the manual once you start you take off right away gradually, instead of letting it warm up. is that ok to do??

Yes, you actually warm the engine up faster when it is under load. Drive it like you own it, not like you stole it, 'til it's warmed up to normal op temp (some say 160 degrees min oil temp. - - that's what it used to be for the e46 m3 IIRC). Lots of people say keep it under 3000 rpm 'til then. Takes about 15 min. If you have the ZF auto tranny and you are in Comfort mode, it's probably programmed to shift at 3k or under anyway.

Too bad BMW doesn't repeat the feature they had on the e46 M3. When cold, the tach showed a ring of red diode lights around the circumference of the tach. The driver was supposed to keep the shift points at or below the red lights. As the engine warmed up, the red lights gradually went out one by one 'til you could flog it with abandon. Made the warm-up process very easy.

[nop]

Baby your car if you want to, I'm not here to tell you otherwise. But consider that if spirited driving really did any damage, BMW would have electronically limited the performance during the break-in period.

[m6pwr]

Originally Posted by nop

Baby your car if you want to, I'm not here to tell you otherwise. But consider that if spirited driving really did any damage, BMW would have electronically limited the performance during the break-in period.

You don't have to baby the car during the break-in period. I've never seen anything in writing by BMW that says you need to baby the car during the first 1200 mi. All they have ever said is to avoid WOT and keep the revs under 4500 (3500 for diesels) for the first 1200 mi. There's plenty of performance (spirited driving?) available under those limits. Of course if the mantle of Nuvolari, Senna, whomever, descends upon you whenever you fire up your new bimmer, you can cane the beejesus out of it from the get go. In fact many people swear that is the proper way to break in a new BMW. BMW gives you your choice; no electronic nannies needed.

[Vegetable]

Originally Posted by m6pwr

You don't have to baby the car during the break-in period. I've never seen anything in writing by BMW that says you need to baby the car during the first 1200 mi. All they have ever said is to avoid WOT and keep the revs under 4500 (3500 for diesels) for the first 1200 mi. There's plenty of performance (spirited driving?) available under those limits. Of course if the mantle of Nuvolari, Senna, whomever, descends upon you whenever you fire up your new bimmer, you can cane the beejesus out of it from the get go. In fact many people swear that is the proper way to break in a new BMW. BMW gives you your choice; no electronic nannies needed.

Oh man.. under 4,500 RPM? and no WOT? I think I'm going to take a long road trip from LA to Seattle on I5 when I get my 435i just to get the 1,200 miles out of the way.. In fact, if that is the recommendation, that is exactly what I am going to do.

[Shakes]

Originally Posted by Vegetable

Oh man.. under 4,500 RPM? and no WOT? I think I'm going to take a long road trip from LA to Seattle on I5 when I get my 435i just to get the 1,200 miles out of the way.. In fact, if that is the recommendation, that is exactly what I am going to do.

what is WOT???

[GregW / Oregon]

Originally Posted by Shakes

what is WOT???

Wide Open Throttle

[GregW / Oregon]

Originally Posted by Vegetable

Oh man.. under 4,500 RPM? and no WOT? I think I'm going to take a long road trip from LA to Seattle on I5 when I get my 435i just to get the 1,200 miles out of the way.. In fact, if that is the recommendation, that is exactly what I am going to do.

Best is varying speeds and rpm, not more or less constant. Also, need to work transmission and brakes more than on the freeway.

[m6pwr]

An added tidbit re the difference between the 1200 break-in on M cars (oil change) and the non M cars that get no 1200 mile oil change:

I did a used oil analysis (UOA) on the 1200 mi drain from my e92 M3 and was quite surprised at what I found. The oil was a thin 5w30 weight (the service fill on the non-turbo M cars as most know is a 10w60). It had a very modest detergent additive pkg and nothing too robust for the antiwear adds either. In other words it appeared to be an old school break-in oil designed to seat (wear-in) the cylinder rings as quickly as possible before the hot shoes (as in some on this forum) started to drive the snot out of the car. And like many break-in oils it was most likely a conventional mineral (non-synthetic) oil. These oils are actually designed to allow controlled but more than normal wear during a brief period. And with the weak detergent pack, they are definitely not suitable for an extended drain interval (10-15k mi), thus the early drain. The wear metals on my UOA incidentally were very low. So much for the myth that the 1200 mi drain is done to "wash out" harmful levels of wear metals.

So this kind of begs the question: Why does BMW do this for M cars and not other BMW's? My uneducated guess is the difference in metallurgy, engine design and operating parameters (e.g. the e92 M3 had silicon-impregnated aluminum cylinder barrels - - very, very hard). In other words, BMW feels the non M BMW's don't need it.

One more tidbit to throw into the Hard Break-in vs Soft Break-in debate: BMW has an interesting site that describes their engine factory in Austria that makes the six cyl N55 gas engines and all their diesel engines. It describes how as a quality control measure all the engines are run briefly on an engine dyno powered by electricity (no mass emissions to choke the towns folks), but some are randomly selected and run under their own power at WOT for an extended period - - called the "dynamic engine audit"! Doesn't say what they do with these engines afterwards. http://www.bmw-steyr.com/index.html

[lugnutm4]

Another thing to remember is that the engine is built without cylinder liners. It has twin-wire arc-spray coating (instead of liners) in cylinder bores. Thus tehre is less material between the piston rings and the aluminum block.