TM  10-3930-638-24&P 2-36.    TRANSMISSION    TROUBLESHOOTING    (cont) MALFUNCTION TEST  OR  INSPECTION CORRECTIVE  ACTION 4. LOSS OF DRIVE IN ALL RANGES Step 1. Check oil level with transmission at operating temperature and engine operating. a. If oil level is not between FULL and ADD marks, add oil (refer to current lubrication order). b. If oil level is between FULL and ADD marks, proceed to step 2. Step 2. Check if axle disconnect lever is in disengaged position (pulled outward). a. If axle disconnect lever is in disengaged position (pulled outward), place in engaged position. b. If axle disconnect lever is in engaged position, proceed to step 3. Step 3. Observe control valve assembly linkage while an assistant moves direction selector and speed selector through their entire range. Movement of control valve assembly forward and reverse and speed selector spools should be observed. a. If movement is not observed, replace/repair cables/linkages (para 2-38b). b. If movement is observed, proceed to step 4. Step 4. Disconnect linkage at control valve assembly valve spools. Start engine, operate at idle speed, and set parking brake. NOTE Do  not  depress  service  brake  pedal.  Depressing  service  brake  pedal activates declutch valve in turn neutralizing transmission. 2-197