A4LD
- Automatic
Transmission
Article
and info courtesy of
The
Ranger Station
and Gloria
Roozen
The
A4LD four speed
overdrive
transmission was
introduced in the
1985 Bronco
II/Ranger and saw
use behind many 4
and 6 cylinder
engines until the
1995 model year when
it was replaced by
the 4R44E and 4R55E
electronic
transmissions.
The A4LD was the
first Ford
transmission to use
an EEC-controlled
torque converter
lock-up clutch and
later became the
first to use
electronic shift
control (via a 3-4
shift solenoid). The
French-built A4LD
was created by
adding overdrive to
the front of the C-3
three-speed unit.
The A4ld has a 2.47
first gear and a
0.75 overdrive.
For 1995, the 4R44E
(4 cyl. -
light-duty) and
4R55E (6 cyl. -
heavy-duty; i.e.
Explorer)
electronically
controlled
transmission
replaced the A4LD.
It is mechanically
identical to the
A4LD.
These four and
five-speed
transmissions are
used in four
cylinder and V-6
applications
(primarily the
Ranger and
Explorer). The A4LD
was derived from the
C-3 three-speed
automatic
transmission by
placing a two-speed
overdrive unit in
front of the
original three-speed
workings. As the
names imply, the
"E"
transmissions are
electronically
controlled (similar
to the AOD-E/4R70W
transmissions),
while the 5R55E is a
five speed version
currently used only
with the SOHC 4.0L
engine. The 4R44E is
a light duty version
of the electronic
unit, similar to the
old non-4.0L A4LD
transmission.
The A4LD is
identified by a
"T"
transmission code.
The overall length
of this transmission
is
28.687-inches.
There are no
adapters available
to swap this
transmission to a
V-8 at this time.
Even
More A4LD
Information
The
A4LD 4-speed,
overdrive
transmission has
been used in the
Ranger/Bronco
II/Explorer platform
since 1986. As most
of the early
overdrive auto
trannies, the A4LD
was not real
reliable in the
early years. The
first major change
came with the
introduction of the
4.0 in 1990. While
still an A4LD, the
4.0 version was
significantly
stronger than the
non 4.0 versions. It
also had a computer
controlled torque
converter lock-up.
In 93.5 another
major upgrade of
this transmission
occurred. In
addition to the
computer controlled
lock-up, the
transmission also
got a computer
controlled overdrive
engagement.
Internally, most of
the thrust washers
were replaced with
torrington bearings,
which made the
tranny much
stronger.
While the A4LD has
gotten a bad rap, it
is actually a good
strong transmission.
The newest version
is still an A4LD, it
just goes by another
name due to the fact
that it is
completely computer
controlled, and has
a 5th gear.
There are
modifications and
upgrades available
to this tranny.
Better grade
clutches and bands,
better converters
with improved
lock-up clutches and
brazed fins (stock
converters were
known for clutch
failures, which
takes out the entire
trans), welded
planetary cages,
shift kits, and the
ability to upgrade a
non 4.0 tranny to
4.0 specs makes this
tranny very
versatile. At its
strongest (off-road
race application),
these transmissions
are holding up to
V6's making in
excess of 300hp.
Once the engines get
much higher than
that (depends on
usage) the main
shafts will start
bending.
One of the most
interesting upgrades
available for this
transmission is the
off-road race
package. This
includes numerous
valve body and
internal
modifications. These
modifications are
easily attainable
from a good tranny
man. What this
modification does
for you, is give you
an automatic with
all of the
advantages of a
manual....... and
none of the
downfalls. Run in
drive, you can split
the 3 gears with
overdrive, and you
can lock-up the
converter in any of
the gears. This
gives a much greater
availability of
ratios, and makes it
real easy to keep
the engine in its
power curve. Also,
because you can
lock-up the
converter whenever
you wish, it also
helps to keep the
transmission cool.
This mod also allows
the transmission to
be used completely
manually.
When having an A4LD
rebuilt, there are a
couple of things
that you need to
make sure of. First
and foremost, do not
let a shop do a soft
parts fix only
(clutches, servos,
and bands). This
will almost ensure
that you will have
another repair
needed right after
the 1-year warranty
is out. Other things
you want to have
replaced are:
forward one-way
clutch (always),
overdrive drum
(stamped tin,
replace if out of
round or heat
damaged), pump (Ford
only, rebuilds are
prone to failure),
and the converter
(get the better
converter with the
improved lock-up
clutch and brazed
fins). Also, get
references from the
shop and call the
people. Just because
they can rebuild
TH350's and C4's
does not mean they
know what they are
doing with overdrive
trannies.
One of the best
things you can do
for your auto tranny
is get the largest,
aftermarket, stacked
plate cooler you can
fit behind your
grille. The factory
cooler is marginal
at best, due to its
being tied in with
your radiator.
Remember, with that
set-up, if you
overheat your
engine, you will
overheat your tranny.
Heat is the biggest
enemy of the
automatic
transmission. Change
your fluid and
filter every year,
or every 12-15,000
miles if used hard.
Use ONLY the fluid
recommended by Ford.
Only use synthetic
fluid if it is
required by Ford.
With proper maint.,
these transmissions
should last well
over 100,000 miles.
- Gloria
Roozen
More Notes
Best I can tell from ATSG manual, the changeover date for single to dual solenoid versions occurred in mid '88 The single solenoid originally on the trans 85-87 controls only the TC lockup function. Later models had the 3-4 shift inhibit solenoid added in 88. And I have both a 90 2.9 A4LD and a 93 Explorer A4LD here, both have the dual solenoid setup.
Tbird A4LD - Problems
Premature
wear or a repeat
failure of the
converter hub, bell
housing bushing,
converter seal
and/or pump assembly
may be caused by a
broken or worn crank
shaft pilot sleeve.
Located between the
flywheel and the
crank-shaft, the
pilot on the front
of the converter is
centered on the hole
in the sleeve.
To avoid these come
backs remove the
flywheel and
visually inspect the
spacer on every 2.8,
2.9, and 4.0 engine
that may be
suspected of having
this problem.
Note:
If the original bell housing bushing is not worn, reuse it. Converter hub to bell housing bushing clearance should be .002"-.003" Converter depth from the front of the pad to front of the bell housing should be 1 5/8" to 1 3/4"
Seal Blow Outs:
If you have repeated front seal blowouts on A4LD's it may not be a problem with the seal or the quality of your work. Your could have a bad bell housing. The bushing used in the A4LD is finished in place. Because of this the bore that the bushing fits into doesn't need to be in the center of the bell housing, and in many cases it isn't. When you're working on an A4LD you need to check the bell housing bushing to see if it's the original factory bushing. If it is, and it's not worn (no more than .003") converter hub to bushing clearance), Don't Replace It! If the bushing needs to be replaced, you need to make sure the replacement bushing will fit in the center of the bell housing. To do this bolt the torque converter to the flex plate. Turn the engine over and check the run out of the converter hub. Now bolt the bell housing to the engine. If the Torque converter is contacting one side of the bushing excessively, the bushing is off center and the bell housing MUST be replaced. However, a slight amount of contact is acceptable. By checking the bell housing first you can avoid repeated front seal blowout.
For
more info please
visit The
Ranger Station Ford
Ranger Automatic
Transmissions Page
or visit their Home
Page at http://www.therangerstation.com
Technical Information Terms Of Use - Disclaimer
Activities and vehicle modifications appearing or described at The Ranger Station and it's pages may be potentially dangerous. We do not endorse any such activity for others or recommend it to any particular person - we simply describe the experiences and opinions of other Ranger/Bronco II owners. If you choose to engage in these activities it is by your own free will and at your own risk. Any and all modifications will likely cause a vehicle to behave differently than stock. Some modifications may significantly increase your risk when driving the vehicle or be dangerous in some driving situations. Use your brain and common sense when engaging in any activity or making any modifications. Do not take unwise risks. Consult a certified professional if you are not sure of something. The Ranger Station and the authors of these articles assume no liability for how any particular individual chooses to use the information presented here. Some of these modifications may void your vehicles warranty.