Fuel problems in the desert not new.

Your article in the April 2004 issue "Truck Crews Get Crash Course in Survival" provided some very informative details on problems occurring with trucks operating in Iraq and how soldiers are adapting to these situations. However, the reported problems occurring with truck engines caused by their consuming JP8 fuel that had been treated with engine oils and automatic transmission fluids needs to be clarified. JP8 fuel, unlike diesel, a distillate fuel, is essentially all kerosene and therefore has a somewhat lower viscosity than diesel fuel. In areas such as the Middle East, the high temperatures cause the viscosity of JP8 fuel to decrease even more. The decreased viscosity of the fuel creates an internal leakage problem within the fuel injection system as well as a lubricity problem with certain types of fuel injection pumps. Both of these problems occurred prior to and during the last two Gulf wars and have been documented.

Past attempts to resolve these problems have involved adding fluids and oils. Before the 1991 Gulf War, units were starting to experience engine problems when using aviation turbine fuel in lieu of diesel fuel. One fuel injector pump manufacturer actually recommended the use of an automatic transmission fluid to reduce the lubricity problems. Researchers at Southwest Research Institute subsequently confirmed that additions of ATF did not improve or correct the lubricity problem. Unfortunately, this "field fix" does not correct any lubricity problem nor will it correct any leakage problem. The result is hot starting/ hot idling problems, loss in power and diminished performance.

As long as the military continues to procure diesel engines manufactured with fuel injection systems having diesel fuel as the primary design fuel and not JP8, continuous use of JP8 in high temperatures environments will create problems.