One of the things to remember about the M35A3 is that is was designed to maximize the use of recycled M35 parts to help it supplement the initial FMTV delivery, so there are compromises made with some stuff like the CTIS implementation on existing Rockwell axles, the automatic transmission having to fit without moving the transfercase back, and 365/80R20 tires so that one super single could fit in the traditional spare tire location with minimal modification and have no rubbing between the tandem axles. So some design decisions that may not make sense were compromises to deliver a modernized truck cheap.