Which type of oil is used for break-in? - The Unofficial BMW M5 Messageboard (m5board.com)

homesite · 25th March 2006, 04:42

What oil is used for breakin and what is used after? Is the breakin oil synthetic?

syn1c · 25th March 2006, 08:59

Mineral oil is used during the break-in period, and then it's changed out for synthetic oil during your 2000km service.

SCORPIO · 25th March 2006, 13:07

I saw some of it when they did my 1200 mile service - it is bright neon green - really weird stuff - but it must work!

Bibendum · 25th March 2006, 15:31

That's weird. I guess some small amount of it will always stay in the engine and will always mix with the synthetic...

spatterso · 25th March 2006, 16:18

Any explanation on the properties of the oil and why it's used instead of synthetic?

bernhtp · 25th March 2006, 16:54

It would be good to have a report from an engineer/metalurgist that specializes in engines. I would speculate that BMW has data to indicate that this non-synthetic wears and finishes the surfaces in ways that synthetics don't and this is particularly beneficial to the seating/sealing process. My bet is that the severe rules within the original 1200-mile period have more to do with the limitations of the oil itself where this type of mineral oil cannot stand the high-rev, high-compression and high-temp rigors of driving the M5 near its potential. So, if you want to "race" the car from the beginning and forego whatever benefits that slow break-in with this non-synthetic confer, change the oil to TWS yourself right away. Racing the engine with an oil specifically not designed for performance use is asking for trouble.

Tom

spatterso · 26th March 2006, 04:13

Tom,
That is probably the most sensible argument I have heard to date for the break-in schedule and for reasons why NOT to step into it hard during the first 1200 miles. I imagine that the next break-in level is harder because it is more attune to conventional wisdom. I appreciate your insight.

Realtycar · 26th March 2006, 18:06

Quote:

Originally Posted by Bibendum

That's weird. I guess some small amount of it will always stay in the engine and will always mix with the synthetic...

The mineral oil will burn out in no time if your going past 6k RPM. This is why eveyone was talking about this car DRINKING OIL, becuase it isn't motor oil!

Fart · 26th March 2006, 21:07

Mine has gone down to .6 in 1700km. Most of my brake in has been done at speeds from 130-170km hour.

M5converter · 27th March 2006, 00:56

I've followed the break-in religiously and I had to fill my car up with more oil today because the gauge said it was at .1L at 2250 miles. Kinda weird...

vndkshn · 27th March 2006, 17:07

I thought the official word from BMW M was that it was not mineral oil, they only change it to get the break-in crud out.