Disc may or may not be as "good" as shoes but, probably are better. Pad surface area is greater and there aren't a dozen or more springs, clips, pins, nails, adjuster wheels, wheel cylinders, bars........to screw with. Much better idea if you can afford the swap. Pretty sweet with power assist and dual MC. Rear brakes don't need disc on our trucks. As said, disc better for heat dissipation and water throw off. The big trucks are switching from drum to disc to meet a "new", mandated, shorter stopping distance requirement.
Excerpts from Dec. 15, 2005, notice of proposed rulemaking
(NPRM) to improve the stopping distance performance
of truck tractors, the National Highway Traffic Safety
Administration (NHTSA)
Increased Use of Air Disc Brakes
While already highly utilized in Europe and in select
North American applications, air disc brakes are
experiencing continued growth in popularity on North American highways with
commercial vehicle fleets and owner-operators. Previously considered a niche
technology for bus, coach, fire trucks, and other special applications, air disc brakes are
becoming increasingly sought out for over-the-road applications.
Bendix experienced a nearly 120 percent increase in demand for these advanced
braking systems from 2009 to 2010. The company added a new assembly line in 2011
to meet increasing demand. In early 2012, Bendix Spicer Foundation Brake reached the
quarter-million milestone on the brake, which it began producing in 2005. The company
surpassed the 400,000-unit mark in early 2013, an increase of more than 60 percent in
just one year.
Industrywide, air disc brakes represent only a 10 percent market share, with drum
brakes encompassing 90 percent. Their acceptance is clearly growing, however,
as evidenced by the ever-increasing output at Bendix. The industry is increasingly
demanding air disc brakes and the higher performance and safety they offer, as well as
their reduced maintenance demands.
