Originally Posted By: SpitfireS
How shear stable are those 10W-60 oils anyway?
I mean, if they shear down to 40 weights within a short time you're better off using a 40 weight that stays a 40 weight to begin with.
From an old post of mine:
This is my neighbor’s 2003 Ferrari Enzo with a total of 8,800 miles on the left column and my 2003 Enzo with a total of 3,000 miles on the right column. Both cars had 1,400 miles on the oil. His obviously had more break-in time. He had the oil changed by the Ferrari dealer using the required 10W60 Shell Helix Ultra Racing oil. I ran 0W30 Castrol GC.
The recommended interval is 5,000 miles, less if on the track. This is strictly off track use in town and on the highway, probably 50-50 for his car and 90 percent city for me.
His oil was tested by:
http://www.youroil.net, while I got the full, total evaluation from Terry Dyson at
http://www.dysonanalysis.com.
................................................................................................................
_____________Shell...GC
Iron___________ 32...11
Chromium ______ Nickel __________ 2...1
Aluminum ______11...3
lead ___________ 16...0
Copper _________25...8
Tin ____________ Silver _________ Titanium _______ Silicon _________ 7...3
Boron __________ 1...3
Sodium _________ 8...3
Potassium ______ Molybdenum ____ Phosphorus ___1026...935
Zinc ________ 1135...1228
Calcium _____ 1454...1671
Barium _______ Magnesium ___1219...526
Antimony _____ Vanadium ______ Fuel %Vol _____ Abs Oxid ______34...10
Abs Nitr _______11...8
Wtr %vol ______ Vis CS 100C __ 15.8...11.8
Vic CS 40C___not done...66
SAE Grade _____40...30
Gly test ______NEG...0.37 “not antifreeze”
TBN _________not done...7.9
aehaas
Today:
Also, I tested the Shell 5W-40 used in the Ferrari Maranello and it quickly thinned from a 40 to a 30 grade as well.
aehaas