Originally Posted By: jdw1222
running rotella synthetic 5w-40 right now. do you think i can go longer on the bypass filter? Still would like to find a cheaper filter i can buy locally. also, i have seen results from several 6.0 used oil analysis and the shearing is always the problem requiring an oil change, not contaminated oil
Yes you can extend your intervals way past the manufactures recommended intervals, but only with the use of a used oil analysis, and the ability to read it properly, I say this cause most all the Oil Analysis interpretstion guides are based on mineral oil with 5000 mile intervals. when you use Synthetics and you have a sample with 25,000 miles and the iron PPM is at 92 most labs will flag the iron and recommend a change.
Not necessary with Synthetic oil, if you divide 92 by 5 you will get 18.4, that will bet your Iron sample every 5000 miles using Synthetic oil well within the Normal Iron level for Diesel engines, wich is 10/40 ppm every 5000 miles
Here is a sample with 22,000 miles on a 6.0 using Amsoil Synthetic blend 15w40 PCO with no bypass filter
Quote:
Aluminum 1
Chromium 4
Iron 92
Copper 21
Lead 26
Tin 3
Moly 10
Potassium 0
Boron 2
Silicon 41
Sodium 0
Calcium 3413
Magnesium 20
Phosphorus 1168
Zinc 1319
cST Viscosity @100 11.76
Fuel TBN 2.18
OXD 23.0
NITR 40.0
F-soot 0.32