When's a car "run in"?

[hoolio]

Another dozzy question that wont concern most people, but i was thinking about g40steve's (hi) comment "have you run it in yet" and having only done 3k from new i don't consider it to be properly run in. When i bought it they advised that i should change the oil at 4k-to get rid of any crap in engine- and after that i was going to get more "aggressive".
Is there any merit/logic to this or am i being way way too cautious?

 

[T7PHY]

I always thought it was after 750 - 1000 miles but then I haven't got my Trophy yet (pick it up next week).

Yours should be well run in by now hoolio. 8)

 

[Nik]

My experience is they just loosen up more and more all the way to 50,000 odd miles.

It was noticable on the rolling road day that we did that the Trophies with more miles on were getting better results (although we're talking 2 or 3 bhp at the wheels or so between 2k cars and 8-9k cars.

 

[oliie]

Guys - just as a side comment: was in the BMW factory in Munich a few weeks ago. Let me quickly explain how BMW run their cars in at the factory (simplified a bit, but factual nonetheless):

1) Chassis (with engine, gearbox) 'married' to body of car
2) Car is completed
3) Engine is started for the first time in the car (odometer shows '000000')
4) Car is driven onto rollers by an engineer
5) Car is subsequently driven to 160 kph on the rollers with a fairly heavy right foot (yep.... 160 kph) for a few minutes
6) Car is driven off rollers
7) Engine is switched off

There you go... brand new engine broken in at the factory

When I bought my 330ci from new, BMW told me I did not need to run it in as it would be pointless. Now I know why

There is a difference between 'loosening up' and 'running in' though in this situation (loosening up will happen irregardless of running in, as a generalisation).

O.

 

[cardealer]

In ye olden days we used to change the oil and filter at 500 miles or thereabouts. as the bearings and rings would be bedded in by then. I did know about the revving the nuts off at the factory, but kept it to myself - it's a bit alarming to tell a civilian that!

 

[MrD06]

most high spec cars use a running in oil which has to be changed at 1000 miles.

also its worth running a car in no matter what people say, as if you let a tight engine labour your in big trouble in the future.

 

[cardealer]

It's a big issue with M3s missing their running in service. You basically get a three hour new BMW handover and nobody mentions you need to go back at 1000 miles

 

[MikeS]

It's a big issue with M3s missing their running in service. You basically get a three hour new BMW handover and nobody mentions you need to go back at 1000 miles

Yep, it's one of the things I checked before buying my M3. BMW dealers also can't give an M3 an extended warranty (the AUC) if the service was missed / late. Doesn't stop some of them trying to sell them though :roll: