TM 9-2320-209-10-1 4-12. OPERATION OF TRACTOR TRUCKS. a. General. Tractor trucks covered in this manual are made to tow a semitrailer with a maximum travel load of 17,000 pounds for cross-country travel and 36,000 pounds for prepared road travel. b. Coupling the Semitrailer. PERSONNEL: TWO FRAME 1 1. Start engine. (Refer to para 4-6b.) 2. Place tractor truck in front of trailer with wheel coupler jaws (1) almost touching and directly in line with semitrailer king pin (2). 3. Place FRONT TRANSMISSION gearshift lever (3) in N position. 4. Pull handbrake lever (4) up to on position. GO TO FRAME 2 4-217