ANNISTON ARMY DEPOT, Ala --Employees overhaul and repair final drives for a variety of vehicles in the Army’s fleet, from the M1 Abrams to the M88 and M113, in the Directorate of Production’s Transmission Drive Gear Division, Final Drive Branch at Anniston Army Depot.
The final drive is a heavy duty, speed reducing gear that connects the transmission output through the hull of the tank to the drive sprocket. Its primary functions are to increase torque and reduce the speed of transmission outputs. And because of the high importance of the component, employees in the area are focused on quality.
In fact, throughout the overhaul process, there are continuous quality checks. “Quality drives the process,” said Spence Beasley, heavy mobile equipment supervisor in the Final Drive Branch. “At every point in the process we’re looking at parts to see if they’re good, bad or need to be replaced. We don’t want anyone in the field needing to take the tracks off and make repairs.”
Tristan Homesley, heavy mobile equipment mechanic and subject matter expert in the area, emphasized just how much the work he and his coworkers do daily matters to the warfighter.
“This process is very important,” Homesley said. “The final drive is one of the main components that makes a tank move. If it’s not working properly, Soldiers will be stranded in the field.”
The overhaul process begins when the final drives arrive in the shop’s loading area. They are then placed on stands where mechanics inspect each one to determine if they can be overhauled or must be scrapped. Those that will be overhauled are then sandblasted and washed.
Once the final drives return to the Final Drive Branch, mechanics begin disassembly. They also inspect parts at this stage for quality.
Next, parts are routed to be washed before they are inspected according to the overhaul inspection procedure in the machine shop. Those parts are then staged where the mechanic will begin pulling their parts for assembly.
Finally, mechanics begin the assembly process, repairing parts that can be fixed or adding new parts when needed. Once the final drives have been reassembled, a mechanic tests them to ensure proper function.
“First, I visually inspect the final drive and then I load it into a machine for more testing,” Homesley explained. “In the machine, I complete a spin test to check for oil leaks.”
The entire process is completed almost exclusively in the Final Drive Branch, including painting of the final drive, final quality testing and shipping. As a result, mechanics in the shop learn a variety of processes. In fact, Beasley stresses the importance of cross training, moving employees to different lines and areas often.
“All of our mechanics have a really good skill set coming in, but a lot of these processes are learned through on-the-job training,” he said. “We really believe in cross-training. I move employees around so they learn both disassembly and assembly. It helps them understand the entire process.”
Homesley echoes the importance of cross training, noting that it is good for everyone.
“It really helps for everyone to have experience working the entire process,” he said. “This keeps those working in disassembly from unintentionally doing things that cause issues when it’s time for other mechanics to reassemble.”
The Final Drive Branch completes nearly 100 final drives monthly, on average. In May, they overhauled 54 finals drives for the M1 Abrams, 49 for the M113 and five for the M88.
“I’m really proud of the work we do each month, especially with the volume we produce,” Beasley said.