[Bimmerdoc54]

Hi guys -

Love the forum, long time lurker. My (long awaited) 340xi m-sport should be coming to port this week, with delivery to me soon after. Question: any official word on the break in period of the new b58 engine? What do people recommend? Thanks!

[goj]

Originally Posted by Bimmerdoc54

Hi guys -

Love the forum, long time lurker. My (long awaited) 340xi m-sport should be coming to port this week, with delivery to me soon after. Question: any official word on the break in period of the new b58 engine? What do people recommend? Thanks!

BMW will probably recommend 1200 miles keeping rpms at or below 4-4.5k.

Mixing in revs higher than that shouldn't be bad, in fact some argue it's good for the break in. I personally would give it about 600 miles before flexing its muscles a bit more.

I'm sure many people will have different formulas for break in but in general I feel like I will be fairly conservative when mine arrives. Not just because of engine break in but more because I will be getting acclimated to a new car.

[F32Fleet]

Technically there's no such thing as break-in for the non-M engines, however I would for the first 20-25 miles try to drive the car in manual mode at various rpms. After the first 25 miles it's over forget about it.

My own anecdotal results with this method is no oil consumption (E90 330 & 335d). Whenever I didn't follow this method I had oil consumption with the car (E46 330zhp)

[Weaselboy]

Originally Posted by Bimmerdoc54

Hi guys -

Love the forum, long time lurker. My (long awaited) 340xi m-sport should be coming to port this week, with delivery to me soon after. Question: any official word on the break in period of the new b58 engine? What do people recommend? Thanks!

Here is what the 335i owners manual PDF says and I just checked the paper manual on my 340i (B58) and the wording is exactly the same.

[Bimmerdoc54]

Great information - thanks a lot guys. I'll post a picture when I get it!

[bucknutz]

I did my full BMW recommended break-in, I figure that people who professionally build cars have a very good idea on what is good for longevity. Also, you're not just breaking in the engine, but every other moving component in your new car.

[Pyewacket69]

Originally Posted by F32Fleet

Technically there's no such thing as break-in for the non-M engines, however I would for the first 20-25 miles try to drive the car in manual mode at various rpms. After the first 25 miles it's over forget about it.

My own anecdotal results with this method is no oil consumption (E90 330 & 335d). Whenever I didn't follow this method I had oil consumption with the car (E46 330zhp)

If that's the case, why does the Owner's Manual say otherwise?

[F32Fleet]

Originally Posted by Pyewacket69

If that's the case, why does the Owner's Manual say otherwise?

Break-in involves at least an oil change and as you can see that's not mentioned in the manual. That's why I said 'technically'.

[HFW003]

Not this old chestnut again.

[BavarianFanatic]

Lol, the motors are dry run at the plant so they're already broken in. Don't beat on it for the first few miles and you'll be fine. As an aside, I did ED with my 335i. So within the first 100 miles it had been on the unlimited sections of the Autobahn multiple times. Zero issues. The more important thing that no one ever seems to address is letting the car get up to temperature before testing it's limits. There's nothing worse for the drivetrain than full loading before evertyhing is warmed up.