6.  Transmission. CAUTION •  Do   not   overfill   trans- mission. The fluid level rises  as  the  fluid  tem- perature increases. There- fore,  do  not check  level before the transmission has reached normal operating temperature.   The   safe operating level is within the crosshatch marks on the dipstick. Overfilling will result in damage to transmission. •  Use Dexron^®  II (3L80) or Dexron^®  III (4L80-E) for filling transmission. Failure to    use    Dexron^®    II    or Dexron^®   III   will   cause damage to transmission. Check  and  fill  transmission  to proper level weekly. Operate trans- mission   through   all   operating ranges to fill cavities and fluid passages. With vehicle positioned on level ground, allow engine to idle, shift transmission to neutral, and apply parking brake. Check fluid level on dipstick. It should register within the crosshatch marks under the conditions stated above. On vehicles equipped for deep water fording, the dipstick has a seal which fits into the opening of the dipstick tube. The dipstick handle must be turned counterclockwise to be   released   before   dipstick   is withdrawn. Turn dipstick handle clockwise to seat after installing dipstick. Have fluid changed every 12,000 mi (19,308 km), or biennially, whichever occurs first. 7.  Crankcase Oil Level. CAUTION •  There are two marks on the dipstick: “FULL” and “ADD 1 QT.”  The  quantity  of  oil required to raise  the oil level from “ADD 1 QT” mark to “FULL” mark is 1 qt (0.9 L). Do not    overfill    crankcase. Overfilling will result in damage to engine. NOTE •  If oil level is above “FULL,” it may be due to oil cooler drain back. Operate the engine for one minute, shut down,  wait one minute, then recheck oil level. •  Oil is added to  crankcase through fill tube which is located on top of engine. Check crankcase oil level daily. Start engine and visually check for oil leaks at drain plug and oil filter. Stop engine and wait approximately one minute for oil to drain back into oil pan, then  recheck oil level with dipstick. On vehicles equipped for deep water fording, the dipstick has a seal which fits into the opening of the dipstick tube. The dipstick handle must be turned counter- clockwise to be released before dipstick is withdrawn. Turn handle clockwise to seat after installing dipstick. Have oil changed every 3,000 mi (4,827 km), or semiannually, whichever occurs first. NOTES G-16 Change 1 TM 9-2320-280-10