Originally posted by johnpr3:
Only a fool would extend drain intervals without doing oil analysis. What happens when you lose an O-ring in a injector, but the oil is still under the mileage warranty? Who'se to blame?
If the vehicle is under warranty, and the failure was due to a manufacturing defect in the O-ring, then the vehicle manufacturer pays.
Originally posted by johnpr3:Case in point - a fleet I work with has been doing extended drains for many years...with great success. A recent oil analysis showed fuel dilution. With that information, they tested other trucks in the fleet. Many trucks in the 800k mile range were starting to show fuel dilution. The problem was quickly identified (O-rings on injectors starting to leak) and taken care of before catastrophic failure. Assuming it was Amsoil in the engine and UOA wasn't necessary and eved discouraged as a waste of money, who would be to blame if they didn't catch the problem in time? My guess is Amsoil would blame the ULSD fuel and, of course, the end user.
Most fleets extend their oil change intervals with the use of UOAs. Many fleets using AMSOIL also use UOAs when extending past the AMSOIL recommendation. In both cases, they usually do not change their oil until the UOA shows they should. In either case, it would show fuel dilution. Some trucks are known to have problems with fuel dilution, and AMSOIL does not recommend extended oil change intervals unless they do UOAs. If the fuel dilution caused the failure, then AMSOIL or any oil would not be liable. However, AMSOIL has shown that their oil holds up better than Rotella, Delo, Mobil and Valvoline with high levels of fuel dilution. See http://www.amsoil.com/lit/g2752.pdf?zo=1181889 for details.
With regards to the mileage warranty, I was refering to the oil.
As for the UOAs. It appeared that you were recommending that money shouldn't be wasted on UOAs when going past OEM recommended service intervals. I am glad to see Amsoil recommends oil analysis for fleets and larger engines.