Helps
to keep your automatic transmission
shifting smoothly.
Drain and replace
transmission fluid
Check start/neutral switch
operation
Road test to evaluate shift
pattern and normal operation
Carry out adjustments
Inspect transmission and
report on any visible leaks
How To Service An
Automatic
Transmission
Step 1 of 14.
Replacement Parts
(service kit) and
Transmission Fluid
Start with proper
tools, transmission
fluid and
transmission filter
service kit. The
service kit includes
a transmission
filter with seal and
pan gasket. All
transmission fluid
varies from car to
car. Consult your
vehicle's owners
manual for your
particular type of
transmission fluid.
Step 2 of 14.
Identify Components
Most automatic
transmissions have a
service pan that
houses the
transmission fluid
and filter. This
transmission has a
heat shield to keep
heat from the
exhaust away from
the transmission.
Some transmission
pans have a fluid
drain plug used to
drain fluid.
Step 3 of 14.
Drain Transmission
Fluid
Drain
transmission fluid:
1.) Insert drain
plug removal tool
and turn counter
clockwise. 2.)
Loosen the drain
plug until easily
removed by hand.
Some transmission do
not have a drain
plug. In this case
the fluid will exit
when the
transmission pan is
removed.
Step 4 of 14.
Drain Transmission
Fluid
After the drain
plug is loosened,
remove plug to drain
transmission fluid
into oil catch pan
then let drain until
completely empty.
Automatic
Transmission
Service
(continued)
(always wear
protective safety
goggles and gloves
before work begins)
Step 5 of 14. Remove
Transmission Pan
When the fluid is
finished draining
remove transmission
pan mounting bolts.
Remove all but two
bolts to hold pan in
place.
Step 6 of 14.
Removing
Transmission Pan
When all but two
bolt remain place
your hand under the
transmission pan and
remove the remaining
bolts. Gently lower
the pan from the
car, you may have to
move a heat shield
or gear selector
cable mount to
remove pan.
Step 7 of 14.
Checking the pan for
Metal Debris
When the fluid pan
is removed inspect
the pan for metal
debris. All
transmissions have
some metal in the
pan but excessive
metal can mean you
are having more
serious problems.
This transmission is
very well maintained
and has little metal
in the pan. Most
transmission pans
have a particle
magnet that traps
metal and keeps it
away from moving
parts.
Step 8 of 14. Clean
Transmission Pan
Fit Gasket
When fitting new
gasket to
transmission pan,
some gaskets are
manufactured with
gasket sealer built
right in, like this
one. If your gasket
is made of cork or
some other style of
gasket you can
elected to install
the gasket with a
gasket fastening
cement. Clean pan
magnet completely
before reassembly.
Step 9 of
14. Changing Transmission Filter
Most
automatic transmissions have a
filter that is located in the
transmission pan. Some filters
are secured to the transmission
with bolts or clips. The
transmission filter in this
photo is held in by a o-ring
seal at the front of the filter.
Grasp the transmission filter
firmly and twist slightly to
remove, fluid will be present in
the filter.
Step 10
of 14. Identify Internal
Transmission Parts
Before
reinstalling transmission pan;
clean the gasket sealing surface
with a shop towel. This enables
a secure seal to the new gasket
when the pan is reinstalled.
While the transmission pan is
remove you can inspect the
electrical connection to the
shift control solenoids. The
control solenoids determine what
gear the transmission is
operating in and are housed in
the valve body. All electrical
connectors inside the
transmission should be secure
for a good electrical
connection.
Step 11
of 14. Re-install New
Transmission Filter
Always
replace the seal for the
transmission filter. Like with
most seals, it is important that
this seal does not leak. If the
transmission filter seal leaks
it can cause the transmission to
ingest air causing low
transmission hydraulic pressure,
allowing the clutch disc's to
slip and cause premature
failure. Re-install filter in
it's proper location, re-bolt or
re-clip as needed.
Step 12
of 14. Re-Install Pan
Carefully
reinstall the transmission pan,
do not damage the gasket on
reassembly or transmission fluid
could leak. Reinstall bolt and
tighten them in sequence one
away from the other and continue
until all pan bolts are snug.
(note: do not over tighten, pan
gasket could flatten out and
leak)
Step 13 of 14.
Remove Transmission
Fluid Level Check
Locate and remove
the transmission
fluid level checker,
in most cars and
trucks this is where
the fluid is checked
and added.
Step 14 of 14.
Refilling
Transmission
Insert fluid funnel
and add transmission
fluid until the
proper amount of
fluid level is
reached. Let engine
warm and recheck
fluid level, add
fluid as needed. Do
not over fill the
transmission, it
could foam the fluid
and cause low fluid
pressure causing
premature
transmission
failure. recheck
transmission for
leaks and recheck
fluid level in a
couple of days.