For sale is a United Tractor SM-40-A9 Tractor Wheeled Warehouse LPG Internal Combustion Engine, Pneumatic Tired. Propane powered! Mod SM-40-A9 SER 16083 Contr. N DLA 700-85-C8166 Cap 4000 Lbs DBP Year 1986 2339 hours GVW 5300 lbs; LG 99"; Wide 65.5"; Hgt - 79"