The M113 is built of 5083 aircraft-quality aluminum alloy, which gives it some of the same strength as steel at a slightly reduced weight, as the greater thickness allows structural stiffness.
Its weight allows the use of a relatively small engine to power the vehicle, a Detroit 6V53 V6 two-stroke diesel engine of 318cuin[REF] with an Allison TX-100-1 three-speed automatic transmission.