Here are the number from an UOA on a 1996 Dodge Cummins. The truck has 132,000 miles on it. It spends 90% of the time towing 4,500lbs. (hardly a load for the truck) in city traffic. FWIW - The truck has been modified with several enhancements to increase fueling and HP.
Miles - 3,848
Copper - 1
Iron - 26
Chromium - 6
Aluminum - 3
Lead - 2
Moly - 3
Phos - 1436
Zinc - 1505
Magnesium - 10
Calcium - 4066
Silicon - 2
Viscosity - 13.31
Soot .1 %
Fuel, H20, and Antifreeze - 0
Sorry I do not have a TBN. Given these numbers the oil could easily run the longer. The reason the oil is changed frequently is mainly becasue of the concern of soot in the oil as it has the ability to lay a pretty dark cloud of smoke with the fueling enhancements.
Miles - 3,848
Copper - 1
Iron - 26
Chromium - 6
Aluminum - 3
Lead - 2
Moly - 3
Phos - 1436
Zinc - 1505
Magnesium - 10
Calcium - 4066
Silicon - 2
Viscosity - 13.31
Soot .1 %
Fuel, H20, and Antifreeze - 0
Sorry I do not have a TBN. Given these numbers the oil could easily run the longer. The reason the oil is changed frequently is mainly becasue of the concern of soot in the oil as it has the ability to lay a pretty dark cloud of smoke with the fueling enhancements.