ment will last the life of the vehicle, pro-
vided it is not damaged.
4.2
Wipe out the filter housing with a clean,
dry, lint-free rag.
5.
Clean and inspect the O-rings and the end cap.
Replace any parts that are damaged.
6.
Install the large O-ring, then the filter element
(small end first) into the filter housing.
7.
Install the small O-ring in the end cap, then in-
stall the end cap on the filter housing. Tighten
the end cap until firm.
8.
Start the engine, and build pressure in the air
system. Check for air leaks at the filter housing
and air line connections, and repair any leaks.
NOTICE
Repair any air leaks. A leaking air filter or air lines
can cause slow or hard shifting of the transmis-
sion, and eventual transmission damage.
26–05 Allison Transmission
Fluid and Filter
Changing
When draining transmission fluid, check for evidence
of dirt or water contamination. A small amount of
condensation will appear in the fluid during operation.
Water contamination is normally characterized as a
milky discoloration of the transmission fluid. Obvious
contamination of the transmission fluid indicates a
leak between the water and fluid areas of the trans-
mission cooler. Inspect and pressure-test the cooler
to confirm the leak; replace leaking transmission
coolers.
1000/2000/2400 Series
1.
Park the vehicle on a level surface and apply the
parking brakes.
2.
Run the engine until the transmission fluid
reaches the operating temperature of 160 to
200°F (71 to 93°C). Shift the transmission to
neutral (N) and shut down the engine.
NOTICE
To prevent dirt from entering the transmission,
use only clean containers and fillers for the trans-
mission fluid. Do not use fillers or containers that
have been used for water or antifreeze. Dirt, water,
or antifreeze could damage the transmission.
3.
Clean the area around the drain plug. Place a
drain pan under the transmission and remove the
drain plug. Examine the fluid while it drains. If
only the filter is being changed, do not drain the
fluid.
NOTE: A lot of fluid will drain when the filter is
removed.
4.
Using a standard strap-type filter wrench, remove
the filter by turning it counterclockwise.
5.
Remove the magnet from the filter attachment
tube or from the top of the filter element.
6.
Clean any metal debris from the magnet. Then,
install the magnet on the filter attachment tube.
7.
Using transmission fluid, lubricate the gasket on
the filter.
8.
Using your hand, install the filter by turning it
clockwise until the filter gasket contacts the con-
verter housing or cooler manifold. Then, turn the
filter one more complete turn.
9.
Install the drain plug and sealing washer. Tighten
the plug 22 to 30 lbf·ft (30 to 40 N·m).
10. Clean the area around the fill tube and remove
the dipstick. Using a clean funnel in the fill tube,
add transmission fluid. See
for approved
transmission lubricants, and
for lubricant
capacities.
11. Check and adjust the fluid level using the appro-
priate Allison Transmission procedure in
MD and HD Series
NOTICE
To prevent dirt from entering the transmission,
use only clean containers and fillers for the trans-
mission fluid. Do not use fillers or containers that
have been used for water or antifreeze. Dirt, water,
or antifreeze could damage the transmission.
Transmission
26
Business Class M2 Maintenance Manual, March 2016
26/7
Property of American Airlines
