ILLARD RUSK OF LITTLETON, CO was first introduced to AMSOIL motor oil in the late
fall of 1972 by a friend while stationed at Ft Hood, TX. The first car Rusk used AMSOIL
in was his 1965 Buick LeSabre. The car was well maintained and had accumulated 65,000
"To find out what AMSOIL would do for me, we first did a thorough tune-up and got
the engine running right to factory specifications," said Rusk. They flushed the engine,
re-checked the engine tuning, and installed a new filter and AMSOIL 10W-40 Synthetic
"After driving around the block a couple of times, I could tell already that the
engine was running better," said Rusk. The proof came when we connected the tachometer
and found that the idle RPM had increased by almost 350 RPM over specification."
After resetting the idle RPM, Rusk continued with his usual record keeping and found
his mileage had increased an average of two to four mpg. After 4,000 miles, Rusk had
a sample of oil tested at an oil analysis lab in Ft Hood that did the analysis for aircraft
oils. Rusk also delivered a fresh sample from an unused gallon container of AMSOIL to
"The people at the analysis lab couldn't believe that the sample form my car had
been in the engine for six months and 4,000 miles," said Rusk. "There was such a negligible
amount of wear materials in the sample from my engine, they thought we had given them
two fresh samples. They actually had me bring my car around so they could draw the sample
themselves and re-run the tests."
The results were the same.
Today Rusk drives a 1980 GMC Sierra Grande one-ton pickup with a 454 ci (7.4L) engine.
Of course he still uses AMSOIL, running Series 2000 20W-50 Racing Oil in the crankcase
and AMSOIL 80W-90 Gear Oil in the differential. The front wheel bearings and all grease
points are lubed with AMSOIL grease.