On 18 September 2000 fielding of M915A4s to ARNG began at Camp Dodge, Johnston, IA. These were the first of the M915s operated within the ARNG to be upgraded under the glider program. The program addressed the primary maintenance cost drivers and reasons for non-mission capable readiness: corrosion, electrical, and transmission.
Assembling an M915A4 simply involved removing the engine, bogy, and pintle from a donor M915 and installing these serviceable components on a glider. A glider is typically a truck without a drive train and rear axle/suspension assembly (or "bogy"). Gliders are being acquired under a multi-year contract with Freightliner, Inc. With this concept the Army was able to upgrade the M915 at about one-half the cost of a completely new truck.
The all new M915A4 glider includes an air conditioned cab mounted on a frame with front axle, wheels and tires, muffler, radiator, fifth wheel, Allison automatic transmission, and front-rear axle hubs (with ABS components installed). It needed only the retained components to be installed to make the M915A4 truck tractor.
Assembly was based on using serviceable donor components with an acceptable remaining service life. Most of the Cummins NTC400 Big Cam I engines in the M915 fleet were known to have reasonably low miles and had performed well over the years. A healthy engine will put out the necessary horsepower.
To assess the engine's health and bring the engine up to the necessary standards for use in the M915A4, an inspection checklist was created. Checklists were also created for the bogy, batteries, and pintle.
The original concept for the M915 Upgrade included retention of the rear wheels and tires. In 2000, the program implemented the Army's Chief of Staff policy directive to phase out dangerous split rims. All bogy wheels and tires were replaced with standard commercial wheels and 11X22.5 radial tires. This eliminated a dangerous and potentially lethal hazard. Converting to newer technology radial tires simplified the inventory process and provided for greater durability, mileage, and fuel economy.
The M915A4 Glider Kit program is a US Army Reserve Command (USARC)-directed conversion of M915 line-haul trucks to a more modern version of the equipment. M915A4 Glider Kit line-haul tractors are assembled at Fort McCoy as part of a US Army Reserve Command-directed program. The program takes usable parts, such as the engine and rear axle, from an M915 line-haul tractor and combines them with an upgraded cab, electronics, automatic transmission, new chassis, front axle, tires and antilock brake systems on the M915A4 Glider Kits. The program saves the government about 50 percent of the cost of a new vehicle and gets the equipment into the hands of units quicker than purchasing a new vehicle.
Army reservists in the maintenance field prepare, rebuild and/or transfer usable equipment, such as rebuilt engines and rear axles, to a new chassis through the Operation Platinum Wrench (OPW) program. The line-haul trucks have up-to-date steering, suspension and braking systems. The time required to complete each conversion depends on the expertise of the soldiers working on the equipment and the number of soldiers working on each vehicle. The soldiers must remove and rebuild engines and rear axles, as necessary, from the old M915 line-haul trucks and install them on the upgraded Glider Kits. source