TM 9-2320-209-10-1 (4) On later model M44A2 series trucks with LD465-1C and LDT 465-1C engines (except M50A2 water tankers), a stack-type exhaust system is used. The upper exhaust pipe (stack) is mounted on the right side of truck and extends above cab top. Figure 2-10. Exhaust System Stack Type, Component location, (LD 465-1C and LDT 465-1C Engines). 2-12