The following appeared in the August 1994 edition of the AMSOIL Dealer Magazine.
AMSOIL INC. and a grocery warehouse conducted a year-long study on the safety and cost-effectiveness of extended oil drain intervals using AMSOIL Synthetic 15W-40 Motor Oil (AME) and the AMSOIL Dual Gard By-Pass Oil Filtration System. The AMSOIL program provided superior engine protection at a lower cost than did the fleet’s traditional program, which included petroleum oil and original equipment oil filters. The traditional program required oil drains at 12,000 miles while the AMSOIL program required no oil drains during the entire study period, with an average 74,000+ miles on each truck’s oil.
Twelve TBN AME offers superior protection against TBN depletion and consequent corrosive cylinder wear. The Dual Gard By-Pass Oil Filtration System also reduces corrosive potential by removing acid-promoting water from the oil, something original equipment filters cannot do. AME retained good TBN/TAN values throughout its extended service life, and low iron and chrome values, indicating
low to normal cylinder wear.
The superior dispersancy of AME and the AMSOIL By-Pass filter’s absolute removal of particles in the one to 20-micron size range offers superior protection against abrasive wear and helps combat soot loading and the oil starvation and cam/lifter fatigue wear soot loading promotes. Though the majority of soot particles are too small to be captured even by by-pass filtration, the reduction in overall contaminant concentration afforded by by-pass filtration promotes greater diffusion of soot particles, rendering them less dangerous. OE filters offer little to no removal of particles smaller than 20 microns. Soot level analysis confirmed the high quality soot control of the AMSOIL program.
The superior Viscosity Index Improver chemistry of AME allowed it to remain well within grade for its entire extended service life. The viscosity specification for 15W-40 oils is 12.5 cSt to 16.3 cSt. Every AME sample retained viscosity within the specification range with the average used oil viscosity for AME a best-scenario, mid-range 14.7 cSt.
Viscosity retention was the critical failing of the fleet’s traditional program. Thirteen of 28 petroleum oil samples, 46 percent, showed viscosities below 12.5 cSt, with an average viscosity of 12.58 cSt. Viscosity loss allows metal-on-metal wear. Sheared viscosity index improver molecules, the product of multi-grade oil viscosity loss, promote ring sticking and other damage.
Clearly, the grocery warehouse fleet safely extended its oil drain Intervals with AMSOIL. It also realized an improvement in cost-effectiveness of approximately 22 percent, based on actual materials costs and industry average labor costs.
Conclusion: the grocery warehouse and AMSOIL demonstrated safe and cost-effective extended oil drain intervals may be obtained using AMSOIL products.