FTER 409,000 MILES WITHOUT AN OIL CHANGE, the AMSOIL-protected Mack E7-400 engine in this truck was as wear-free as an engine in comparable service treated to twenty times the oil changes.

Colonial Heights, Virginia -- "I didn't see any surprises in there at all. Based on what we had with the V-8, it came out the way we expected," said owner/operator Haywood Gray of his 1990 Mack E7-400 engine.

It came out in good shape, exactly what you'd expect for a well-maintained engine with 600,000 miles -- yet the engine's oil had not been changed for 409,000 miles! Here's the story:

Gray began using AMSOIL Synthetic Heavy-Duty Diesel and Marine 15W-40 Motor Oil (AME) in the E9-400 V-8 engine of a 1984 Mack truck after the engine accumulated 45,000 miles. For 280,000 miles, Gray changed his oil at 40,000 to 60,000 mile intervals though his oil analysis reports showed, without exception, that the oil was good for continued use. At 325,000 miles, Gray increased his oil drain interval to 100,000 miles.

The engine was torn down at 600,000 miles when Gray decided to sell the truck. The cylinder liners, bearings, pistons, rings and oil pump, all treated to extended oil drain intervals, were found to be in excellent condition.

Gray continued using AMSOIL AME in the engine of his new truck, a 1990 Mack with a E7-400 engine. With the new truck, instead of using 100,000 mile drain intervals, Gray began basing his oil drains on the findings of a used oil analysis program.

After 630,000 miles total and 409,000 miles without an oil change, the E7-400 engine was torn down by the local Mack dealership in December 1996 and its parts were examined by an engine rater from Lubrizol, a major oil additive manufacturer.

(Read about what "Woody" Gray is doing now, HERE.

After over 600,000 miles, the last 409,000 on the SAME Synthetic Oil the pistons, rings, cylinders, crossheads and bearings show hardly any wear!

Additionally, lead and iron content was far below expected levels according to synthetic oil analysis that was done on the oil from this truck. The following two charts show that AMSOIL Heavy-Duty Diesel Oil, even after going 409,000 Miles using an AMSOIL bypass oil filter, still was well within the acceptable limits according to Mack specifications. In fact, you will notice that the lead content is was less than one sixth of the limit required by Mack specifications.

Looking to the left you will also notice that the iron content is at only about 1/3 the limit required by Mack specs. That's after 409,000 miles on the same oil, folks! By simply changing a couple of filters every 25,000 miles and doing an oil analysis each time, Haywood Gray probably saved himself over 1,000 quart s of oil and about 30 hours worth of work. Do you think he put those thirty hours to good use? I would have.

The engine showed light to moderate wear throughout, just as an engine in similar service and lubricated with conventional oil changed at 15,000 to 20,000 mile intervals would show. In fact, according to the engine rater, the parts he examined -- cylinder liners, pistons, rings, bearings, valve train components -- could have been put right back in the engine and would have continued to provide the good, dependable service they had provided all along -- after 409,000 miles without an oil change!

• HDD Series 3000 5W-30 Heavy Duty Diesel Oil
• AME 15W-40 Heavy Duty Diesel & Marine Oil
• SAE 30 Diesel Oil
• Synthetic Gear Lubes (API GL2-5, API MT-1): 75W-90 (especially our new Series 2000 75W-90/75W-140), 80W-90, 85W-140. All of these products will assist in obtaining higher fuel mileage, have long drain intervals and help to avoid costly repairs.
• Diesel Fuel Additive Concentrate and Cetane Boost also will increase fuel mileage and cut operating costs for truck owner operators.