Seeking THE ANSWER on 'breaking-in' a new BIMMER! - BMW Forum

ConnieLynnGus · 12-04-2003, 05:48 AM

Can someone PLEASE help provide the definitive answer to the break-in question!
I have now seen too many varied opinions about how to go about breaking in a new bimmer. Some people describe a progressive breaking in over 1500 miles while never exceeding 65 mph. Others (including the Owner's Manual) describe a break in period over the first 1250 miles, where the revs should be kept below 4000, speed below 100mph, and constantly varying both engine speeds and travel speeds.
I am not a sophisticated car guy, so I need to know--once and for all--what's the best way to do this?
Also, the dealer told me that there's no need to change the oil early on. I have been an Audi guy for a while before now, and with those, you were always encouraged to get the oil changed early on to remove the "break-in" oil.
What's the consensus???

If it matters, my new wheels are a 330i performance.

Thanks, ConnieLynGus

Mach 5 · 12-04-2003, 06:59 AM

I would follow the instructions in the owners manual for proper breaking procedure. As for the early oil change, as it is difficult to run-in an engine with synthetic oil the factory preruns the motors with conventional oil and then drains and replaces it with the synthetic that is currently in the crankcase.
Ben

peterkulesza · 12-04-2003, 11:06 PM

the manual is correct. you need to vary the load so that the pistons fit themselves into the bore. low revs (PER MANUAL) are good cos hi revs cause scoring of the cylinder wall.

so many people talk about this pre-running oil i have to believe it. i have not seen it on any bmw literature (can the previous poster provide a reference that they really do this ??).

historically, two decades ago or so, cars indeed had break-in oil of different viscosity. that needed to be drained, and manual told you to do it.

one last tip: short trips (engine does not reach temp, under 10 mins) are bad. some h20 condenstation always happens and it creats an emulsion until engine heat drives it off. that emulsion is bad for new bearings.

peter

p.s. i have the same car, it SOOOO rules. damn it rules.

ConnieLynnGus · 12-05-2003, 05:50 AM

Thanks for the info!

As for the short trips and condensation, not a problem--I have a long ass commute. Consequently, the whole of my break in period will be 3 weeks (which will be ending this weekend!)