[Erich]

Kopiert aus roadfly. sehr interessant:

15,000 mile oil analyses results!
The Previous Owner of my 1989 735iL owned the car for 17,000 miles and only changed the oil once. The last oil change was at 140,781 miles, the mileage at time of sample was 155,909 which equals 15,128 on the Mobil 1 SuperSyn 10W-30 oil. BTW, this is NOT the correct weight oil for the M30 in my climate, 15W-50 would have been the correct weight. I decided to send the oil in for analyses. I just got the results today and thought I would share them will all of you.
The results are as follows:

Iron:38
Chromium:2
Lead:5
Copper:18
Tin:0
Aluminum:13
Nickel:0
Silver:0
Silicon:2
Boron:106
Sodium:23
Magnesium:52
Calcium:3062
Barium:0
Phosphorus:1116
Zinc:1297
Molybdenum:81
Titanium:0
Vanadium:0
Potassium:0

Fuel(%vol):<1
Vis.@100C:10.91
Water(%vol):0
Glycol:NEG
TBN:8.60
OXID:14.0
NITR:13.0

Analyses Recommendations:
NO CORRECTIVE ACTION REQUIRED. OIL IS SUITABLE FOR CONTINUED USED. RESAMPLE AT NEXT REGULAR INTERVAL.

BTW, I changed the oil before I even got the results and I am still going to change my oil at 4k.