This is the 3rd UOA I've done on this vehicle and the 2nd I've done on this load of oil.
The reason I do used oil analysis is so we all can learn something, and I find it interesting. Also, since most motorhomes don't see many miles per year, UOA proves to me that there isn't any need to do annual oil and filter changes like the engine and motorhome builders suggest.
This analysis is about Chevron Delo 400 LE. The oil was 36 mths old, w/7500 miles. This bus chassis is a 1995 Prevost 40' XL, motorhome conversion by Liberty Coaches in 1996. The engine is a 1995 Detroit Diesel Corp 12.7L 60 series 470hp that has 83,900 miles since new. The engine oil sump is 10 gals. No make-up oil was added. Most of the miles it sees is running back and fourth between San Antonio and the Colorado mtns in the heat of the summer pulling a 7500 Lbs enclosed trailer. Total combined wt is about 48,000 Lbs. It averages about 7.5 mpg @ 64 mph.
I use dual Fleetguard LF9620 Venturi Combo oil filters. The air filter was a Fleetguard, 50 mths old, w/16k miles.
This oil was relatively cheap and readily available at WalMart. I liked these results. The additive package had some life left in it with a TBN of 4.09. This oil starts life with a TBN of 10. Detroit recommends not depleting the TBN any lower than 2/3rds of what it was new(10), which would be no lower than 3.33. My personal lower limit for TBN is 2.0. IMO.
A couple of weeks after I received this UOA report, I changed the oil w/conventional Mobil Delvac Super 1300 15-40w, 2 more LF9620s, and a Donaldson Blue air filter. Mobil has a heck of a rebate program going on thru the end of 2018 on their Delvac products. https://apfco.com/secure/R9722W/ I'm taking advantage of it.
LAB: Oil Analyzers Inc - OAI(Polaris Laboratories)
LAB COMMENTS: Data indicates no abnormal finding. Resample at normal interval
What do ya think?
Code
Iron 15 Chromium 0 Copper 3 Tin 1 Lead 1 Chrom 0 Nickel 0 Alum 2 Silver 0 Cadmium 0 Vanadium 0 CONTAMINANT METALS-PPM Silicon 8 Sodium 2 Potassium 0 MULTI SOURCE METALS Manganese 0 Titan 0 Molybdenum 74 Antim 0 Lithium 0 Boron 371 ADDITIVE METALS-PPM Magnesium 326 Calcium 1534 Barium 0 Phosph 1005 Zinc 1138 V100C 13.4 IR Oxidation 14 IR Nitra 7 TBN 4.09 Fuel <1% estimate Soot Vol <.2% Water Vol <.1% FTIR
