Gravely 996122 Owner's/Operator's Manual page 36

Level Check
Oil must be drained and refilled with proper quantities to
ensure correct oil level in the front differential case. Check
rear trans-axle case and center transfer case oil at the fill
plug with a clean rod. The rod should be long enough so that
it will not fall pass the fill opening.
1. Park vehicle on a level surface, set park brake, turn off
ignition switch and remove switch key.
2. Remove fill cap and measure from top of fill hole to oil
level in case. This should be approximately 4 1/2"
(11.4 cm) for rear trans-axle case, 2" (5.08 cm) for
center transfer case and 1/4" (0.64 cm) from bottom of
fill opening for front differential case.
3. Add correct lubrication if needed. (Don't overfill.)
4. Replace fill cap and tighten securely.
Oil Change
Warm oil drains quickly and completely. Drain used oil while
it is still warm as follows:
1. Park vehicle on a level surface, set park brake, turn off
ignition switch and remove switch key.
2. Place a suitable container below housing to catch used
oil. Remove fill cap and drain plug.
3. Allow used oil to drain completely and then reinstall
drain plug and tighten securely.
4. Dispose of used oil in a manner that is compatible with
the environment. Do not throw used oil in the trash,
pour it on the ground, or down a drain.
5. Fill gear cases per capacities in SPECIFICATIONS on
page 44.
6. Replace fill cap and tighten securely.
Rear Trans-axle Case
Refer to Figure 33 & Figure 34:
See also SPECIFICATIONS on page 44.
NOTE: Running trans-axle or drive line gearboxes low on oil
can damage seals, bearings and gears voiding warranty for
the trans-axle and gearboxes.
Fill cap location: Top center rear side (See Figure 33)
Drain plug location: At bottom left side (see Figure 34)
Type of lubrication: Mobil 424
Trans-axle case oil capacity: 20 oz. (0.6L)
Quantity: Fill to center line of output shaft.
(Approximately 4 1/2" from top of fill opening to top of
oil level.)
6 mo/100 hrs
Check and Fill Plug
Rear Trans-axle Check and Fill Plug
24707b
Rear Trans-axle Drain Plug
Center Transfer Case
(4-Wheel Units Only)
Refer to Figure 35:
See SPECIFICATIONS on page 44.
Fill cap location: Top center (See arrow)
Drain plug location: Bottom Hex socket screw
Type of lubrication: 80/90 Gear Lube
Center transfer case oil capacity: 6 oz. (0.18L)
Quantity: Fill to center line of output shaft.
(Approximately 2" from top of fill opening to top of oil
level.)
GB-36
24707a
Figure 33
Drain Plug
Figure 34
6 mo/100 hrs