Machine description: 300HP WATER TRUCK, 4,000 GALLON, 6 SPEED TRANSMISSION, 44” REARS, AIR OVER HYDRAULIC SPRAY BARS, NEW CLUTCH, SIDE MOUNTED 4” HOSE AND REEL SYSTEM, 4412 HOURS, ***NOT SOLD WITHOUT WATER TANK***... more info about the 1986 Mack R686ST.