TM 9-2520-246-34-1 GO TO FRAME 2 j. Shifter Shaft Cover. FRAME 1 1. 2. 3. 4. 5. NOTE Transmission is in neutral position when mainshaft (1) turns and input shaft (2) does not turn. Push second and third speed synchronizer (3) towards center of transmission to take it out of mesh. Push first and reverse gear (4) to front so first and reverse gear does not mesh with reverse idler gear in transmission. Do backlash check. Refer to para 2-4b. If backlash check is within given limits, go to frame 2. If backlash check is not within given limits, disassemble transmission and do wear limit inspection. Refer to para 2-4 and para 2-8. 2-103