The Great Transmission Swap
Pedal assembly, (brake & clutch)
Clutch master and slave cylinder
Hydraulic clutch line
3-piece rear crossmember
Recommended: engine and transmission mounts
Day 1, Thursday, February 14th.
I took half of the day off to get to SLC and get started. This
day was one Id been looking forward to for some time; I was excited
to get the project going.
I arrived close to 1PM, and we pulled the car in shortly thereafter.
We looked over the parts again, still not sure if we had everything
we needed. Parts I knew wed need included a clutch hose
that went from the master to slave cylinder. This was supposedly
coming, but hadnt yet. Id received some crossmembers that
werent originally sent on the day before, so we went to work.
Charlie began disassembling stuff on the topside, removing the top engine
pivot mount and a few other items. This is when I finally decided
that I needed to make sure the clutch hose was coming. I called
and was informed that the hose wasnt in stock and was on national
back order, oops. I was a bit disappointed, and Charlie was hesitant
to start into the project while missing such a crucial part. Unfortunately
it would not be the last important part to be missing.
Since Charlie also had some other work to do, he decided that the best
thing to do would be to hold off on the project till the next day.
In the meantime, I went around to a few places, looking for anything
that would fit the line. It turns out that its basically
a brake line, but shorter. Both ends are exactly like those youll
find on a standard brake line, with a banjo fitting on one end, and
female threaded screw-down type on the other. Salvage yards wouldnt
sell me hydraulic lines, but an extremely helpful gentleman at the Murray
Pep Boys let us dig through his inventory, where we found a number of
candidates. I purchased a Raybestos line, content that it would
do the job.
Meanwhile, a later model clutch line was being sent to me by mail, hopefully
arriving the next day.
Day 2, Friday February 15th
6am was the agreed upon time for starting the work, though Charlie had
been there at least an hour earlier. Hed removed the mount,
turbo chimney and lower arm bar. Also disconnected were the lower
ball joints, so that the axles could be pulled outward and away from
the splines on the transmission. At this point we discovered that
the inner CV boot on the right front side was recently torn. A
replacement Subaru boot was ordered and delivered.
Next to come out was the downpipe. Five bolts up on the turbo,
two on the transmission and another two on the flexible joint.
There was another mount, but it had broken off at some earlier date
and was rattling around, trapped by the shielding. The mount was
re-welded in place. At this point it became obvious how pathetic
the stock downpipe really is. Its at least 2, but
it allows for no smoothness from the wastegate and makes a terrible
angle when it turns toward the back of the car. A much smoother,
larger replacement would be much better suited, while replacement of
the catalytic converter itself should yield some benefits when placed
later in the system and replaced with a higher flow version.
The driveline was removed as a whole. The rear portion can be
re-used, as the front is simply a bit longer for the manual version.
We eventually replaced the whole unit, as theyre usually balanced
on assembly, and it just seemed like the sensible thing to do at the
Now with everything disconnected from the transmission, it was time
for it to be removed. A transmission jack was employed to keep
it steady, while strapped down. The rear crossmember was unbolted
and the four mounting bolts holding the transmission were removed.
Also at this time, the four bolts holding the Torque Converter to the
flex plate were removed through the hole previously occupied by the
starter motor. The transmission will not likely come off without
At this point I was getting really excited, there was no turning back
now. With the transmission out, we could actually see how much
larger and heavier it was than the 5MT that would replace it.
Its much wider on the bottom, longer, and generally bigger in
every way than the 5MT. Given the amount of fluid it uses throughout
the system, the weight savings were really starting to add up.
How much would the removal of weight over the front axle improve performance
and handling? These were the kinds of things running through my
Part of the process of actually removing the transmission involved a
device that ran front one side of the engine bay to the other and had
a J-hook running down from it. This hook went through an eyehole
right next to the alternator. The bolt was then cranked up, pulling
the front of the engine upwards and allowing the transmission to be
removed easily. This is necessary for both removal and installation
of the transmission. Ive heard of shops using a 2x4 to accomplish
the same thing. While not nearly as elegant, it seems to do the
Charlie suggested that I get to work removing and installing the pedals
while he replaced the CV boot on a Saab 9000. Pleased that I could
at least get my hands a bit dirty on this job, I went at it. Removing
the stock brake assembly isnt hard, but it sure isnt easy.
Six bolts hold the pedal in, as well as the clevis pin for the master
cylinder. Five of the bolts are relatively easy to get to, after
removing the cover underneath the steering wheel. The sixth bolt
is decidedly difficult to get at, since the brake pedal and the steering
column limit access to it. A little bit of tweaking by Charlie
eventually got it out.
Installing the new pedal assembly included one of those moments when
you think nobody said anything about this! I removed
the shift lock/buzzer box that was right behind the steering column
and the TCU in an attempt to get the pedal assembly to go in.
I quickly ran up against a problem. The master cylinder piston
goes through an O-shaped hole in the assembly. This hole is plenty
big, but its also solidly an O. There was no way to realistically
push in the piston, so we came to the conclusion that removing the Master
Cylinder and vacuum assist was the only way to get it in. Removing
these and pulling them toward the front of the car did the trick, but
I also had to remove the left side of my strut tower brace and relocate
my DIS-2. It also meant bleeding the brakes, ugh.
Installing the pedals also involved removing the gas pedal, and more
work for Charlie trying to get wiring harnesses out of the way.
Once the pedals were in, the same bolts were used to mount the assembly,
though an additional one was needed above the gas pedal.
The shifter assembly was relatively easy to remove. Two screws
in the elbow storage box and two all the way in the front were all that
we could see at first, but the center section revealed no more.
It turns out that this section needs a bit of prodding to pop out, where
two additional screws are located, almost in the center. Be careful
when removing the center part, the plastic can be marred easily if forced
too hard. Removal of the shifter itself was just six screws and
a nut or two underneath on the transmission. There are also three
sets of wires leading off to the right side. One is power, one
is a park position sensor, and Im thinking the third is a reverse
indicator, though it could also be the manual mode lead.
Alex has more information on these; Ill update it when I find
out what everything is.
In order to get the shifter out in one piece, removing the ABS box right
in front of it is necessary. There are four torx-type bolts holding
it down, but unfortunately the left front bolt is concealed under the
wiring harness to the ABS unit. This harness is a little tricky
to get off. An alternative would be to remove the bolt holding
the assembly together in the rear, right under the shifter. This
would probably break the unit into two parts and make the ABS box removal
unnecessary. Either way, it comes out.
Installing the new shifter does involve some work under the car.
At the rear of the shifter is a bracket that attaches to the body, right
behind the shifter in the tunnel. Charlie had me hold the shifter
assembly in place while he lifter the car and installed the bolts into
the holes. Thank goodness all of the holes are there for both
MT and AT versions! The same six screws are used to cinch the
assembly to the center console. In reassembly, I realized that
the MT and AT center section were indeed different. The AT is
much more elongated and the boot wouldnt fit. Im going
to have to find a black MT center section now; in the meantime I get
to see the whole assembly in its nakedness.
Finally we were ready to install the MT, but we quickly realized that
we didnt have all of the crossmembers we needed. The transmission
mount, while attached, was both in questionable condition, and only
attached with one bolt. Having a Lowes home improvement
center within walking distance again proved invaluable, but we were
missing more than bolts.
The rear assembly is composed of three parts, two laterals and one longitudinal.
In other words, its an H-shape, with the tranny mount attaching
just forward of the center point on the crossing bar. The problem
was that we were entirely missing the rear section. This wasnt
good, not at all, because while the transmission could be installed
without it, it would surely be able to shake even more. This was
another one of those moments that we dread. I called and explained
to John that we were missing some more pieces, but I was in a bit of
a panic because it was Friday. While Saturday Delivery was an
option, it wasnt likely to go very smoothly due to the Olympics
in town and enhanced security. What to do?
Thankfully, Charlies shop is in the midst of a large alley
of car repair shops, which included a salvage yard. We hurried
down to the yard and were relieved to find that they indeed had a replacement
crossmember assembly. It seems that all Legacy and Imprezas use
the same crossmember, since the transmission is the same as well.
$20 later, and smiling with relief, we returned to the shop and dropped
off the parts. It was well into the afternoon, and Charlie had
been working for the whole day.
Saturday, February 16th.
We began what we hoped was the final leg of the process at about 9AM.
With the proper parts to mount the transmission, we began the process
of installing the flywheel and clutch assembly.
Early in my swap planning, Id neglected to realize how important
a new clutch was in the grand scheme of things. I'd figured
that I could use the used clutch and flywheel for a while, and then
simply replace them with aftermarket upgraded parts later. After
some research into the subject, it quickly became obvious that I should
really do it all while the opportunity presented itself. Pay for
the parts now and get the install over, or pat $300-500 for install
later. Thankfully fundage was available to get the necessary parts.
On the flywheel side, it's common knowledge that a lightened flywheel
is a good thing in 9/10 cases. The stock flywheel weighs anywhere
from 22-26lbs, while most light versions are 8-14lbs. There are
both lightened stock units, aluminum and chrome-moly units available
from any number of sources. Lightened flywheels are not a great
idea, so the general consensus goes, because removing a sizeable amount
of material from such a precision part can occasionally expose defects
and problems in the original metal. That was quickly dismissed
as an option.
Aluminum is definitely a light metal, and some companies use it for
flywheels. The problem with bare aluminum is that it wears like
nobody's business. The only realistic application of a bare
aluminum flywheel would be in a situation where the transmission would
be removed frequently. Other companies offer aluminum versions
with replaceable facing made of a more resilient material. This
is a reasonable option, but still not the best.
I eventually decided on a Chrome-Moly alloy version from one of a host
of manufacturers. I was impressed by the JUN, Exedy and Fidanza
parts available. Fate stepped in, however, and an I-club member
in Florida by the name of Sunrise City Rider happened to have a brand
new Exedy flywheel meant for a WRX that he was desperate to relieve
himself of. The price was right, significantly less than the price
advertised elsewhere on a multitude of sites. In a few days, my
new Exedy flywheel was in my hands. This is light? I guess
Brennan of SubySports was kind enough to inform me that the WRX and
Legacy share the same flywheel bolt pattern, while the Impreza apparently
uses a different one. Keep this well in mind when purchasing a
On the clutch front, things were more complex. So many companies
had so many products to offer, but which one was a good compromise for
drivability, wear and power handling. In the early rush of turbocharged
2.5Rses, ACT was a popular clutch to use as a replacement for the stock
unit. Time passed, and many trannies later; ACT is regarded frequently
as a transmission killer. Clutchmasters' Stage one and Stage
three were also put forward as very good options with respect to my
needs. Several other brands were also considered, but I decided
against all of these.
The Legacy turbo transmission was unique in the US until the introduction
of the WRX. It was basically the transmission from the overseas
Legacy RS. Instead of the clutch fork pushing forward, the turbo
version pulled away from the flywheel to disengage the clutch.
It was also the only version to use a hydraulic system instead of cable
operation. This meant that the pressure plate was completely different.
Remarkably, the introduction of the WRX probably made the availability
of aftermarket clutches for the Turbo much more prevalent, as they use
the same exact system.
While ranting on the LegacyWorks forum about deciding what clutch to
get, Jason Grahn suggested I call Richard Buckner to see what he recommended.
Richard works for Royal Subaru in Oregon and has an incredible amount
of hands-on experience with the budding SCCA ProRally scene as well
as the other US and Canadian programs. This presents him with
unique insight into what works and what doesn't under stress.
I called and talked to Richard and he informed me that Paul Eklund of
Primitive Racing had previously had problems with the ACT clutch in
his EJ22T equipped rally Impreza. Richard recommended the non-US
WRX pressure plate and it's still running on the car, almost two
years later. I was sold. Richard also recommended the Group
N clutch disc as a good upgrade from the standard version, without getting
a hard feeling take-up. A new Pilot and Throw-out bearing were
Installing the Flywheel was a cinch. Since it's balanced
from the factory, it's not necessary to line it up in any particular
way, so the eight bolts were installed, along with the pilot bearing.
The clutch was put in place with the aligning tool, while the pressure
plate and TOB were assembled. Keep in mind that the TOB needs
to be installed on the pressure plate before it's installed onto
the flywheel. The pull nature of the assembly means
that the TOB is pulled towards the rear of the car and needs to hook
around the center of the pressure plate.
With these part installed, the transmission was prepared for installation.
Two dowels were installed into the engine to help align the bolts.
With the crossmembers installed, the MT was placed onto the transmission
jack and strapped down. The engine was also re-tilted in order
to facilitate the install.
Before installing the transmission, however, the clutch fork has to
be detached so it can be fitted over the TOB. There's a hex-head
plug on the left side that needs to be removed, then the pivot shaft
can be removed and the fork pulled upwards. Once the transmission
is installed, the fork is maneuvered into position from above and re-secured.
Installation is pretty straightforward; just move the tranny forward
till it engages into the clutch and mates solidly with the engine.
Backing off or removing the engine hoist will help the crossmember install,
and the transmission is not going anywhere if it's securely attached
to the engine.
Again, while the rear portion of the driveline is identical to the AT
model, we decided to replace the entire assembly rather early on, so
we went about preparing it and installing. There's a single
crossmember next to the yolk and simple bolt/nut attachments at all
three connections. Simple work.
Before reinstalling the halfshafts, the torn CV boot had to be replaced.
This involved removing it entirely, so the wheel came off, and the nut
on the spindle was removed. The shaft came out pretty easily,
it's amazing how simply this work is done with the right tools,
and pneumatic ones at that. The clips were removed from the old
boot and the bearing assembly was removed. Since the bearings
still had a good amount of grease, we were confident that the unit was
still at least in good shape, without inspecting it too closely.
Instead of using light grease, Charlie informed me that the later Legacies
had a problem with the grease being too thin and leaking out of the
bearings. Instead, he used heavier, reddish grease, packing it
into the bearing cover. He then forced the cover over the bearings
while they were on the shaft. This had the effect of pushing a
great deal of the old, dirty grease out from the bearings. Cool.
With that task completed, the reinstallation of the shafts was continued.
This area is where one can cause problems by installing the pins incorrectly.
There is only one right way to install the pins, and if
done improperly, the pins will go in, but might never come out.
Charlie used a tool with a cylindrical shaft to make sure that the shaft
and splines were indeed aligned properly and installed the pins.
After the halfshaft install, the ball joints were reinstalled and all
bolts, connections and fittings were re-checked. Finally, the
downpipe was reinstalled onto the turbo and exhaust. Unfortunately,
the brackets on the downpipe were meant to attach to those on the AT,
whereas the MT has different attachment points. Since we had limited
facilities, and the welding shop was closed, we simply made sure the
pipe was as secure as it could be made at the moment. The lower
arm bar was reinstalled and again, everything was checked over.
One of our concerns was whether the speedometer cable would reach, since
the AT's attachment point was much closer to the front left side
of the transmission than that of the MT. Thankfully, the cable
had no problems reaching. It does take a little tinkering to get
to fit well over the tube, however, as the first time we drove it, it
wasn't working at all.
At this point, Charlie installed the clutch fork and began to connect
the clutch hydraulic cable. The Master cylinder soon went in and
everything was cinched down. The brake master cylinder was then
reinstalled and attached to the pedals. The ignition was put back
in place, the strut tower bar reinstalled, the rear pivot mount was
installed and the intake replaced. The chimney was also put on
with some new bolts, as most of the old ones were very rusted.
Also remember to reconnect the throttle cable if you disconnected it
when removing and installing the pedal assembly.
Another one of those moments occurred at this time. I'd taken
a walk to the friendly Lowe's hardware store again, to get those
replacement bolt for the turbo chimney, when a couple of friends came
in and told me that the starter motor was different. Oh great.
Here I was in the waning part of the project and something like this
had to happen. In the back of my mind, I considered the possibility
that I would need a different one, but never dwelled on it long enough
to check it out. We took off towards the salvage yard, only to
find that they were closed on Saturday. Well, they had to take
off, so I was dropped back at Charlie's shop, with a genuinely
daunting problem to overcome.
Calls were made to several dealerships; rebuild shops and parts stores,
with displeasing results. It seems that the MT model was almost
completely unavailable in the state. I was quoted anywhere from
$109 with core to $225 without, and everywhere in between. Tired
and mildly depressed at this point, I decided that my only option was
to drive to the local pick-n-pull and see if they had a
Legacy or Impreza. The problem was, would they have, either in
an MT, and if so, would the engine or starter still be present?
Needing a starter, I got a few tools and took off in the MT Astrovan,
determined somewhat to get a starter. I wasn't too confident
that they'd have one, based on my luck during the project.
After paying my $2 to get in, I proceeded to the misc Jap
section and searched for some newer Subarus among the earlier models,
Mitsubishis and Mazdas. It's telling when Hyundai's
section is larger than misc Jap in its entirely. Car
after car I searched, finding one after another Legacy, but all automatic.
It was looking bad, but off in the distance was a beige wagon that held
my last hope. Sure enough, it was an MT. Incredibly, it
had both the engine and starter, so I got right to work. First
I detached the electrical connectors and got a 14mm socket to remove
the top bolt. It was tight, but came out pretty easily.
This bolt is needed with the starter itself, because it's a different
length than the AT version, I think.
The bottom nut, however, would prove a daunting task indeed. It's
on the bottom, but about 8 inches from the back of the starter itself.
I had an extension that was a perfect length, but no matter how hard
I cranked, it wouldn't budge, It even felt as if it were rounding
the nut a few times, the worst thing that could have happened.
The socket I was using was not a new one. Its edges were slightly
rounded and not holding very secure. Not only was I using a bad
socket, but also an 8 extension and ratchet made for a wobbly
fit. It was also in the mid-30s, beginning to get overcast and
with a slight wind. I even tried maneuvering the ratchet so I
could attach the socket directly to it. While this worked, even
putting my entire weight on the ratchet proved ineffective. I
was cold, pissed off and tired.
Back at Charlie's I grabbed a short length of pipe and a 24
breaker bar, resigned to the fact that if these tools didn't get
the job dine, nothing short of removing the engine would get it out.
After attaching the extension and same socket to the bar, I tested the
fit. It felt much better than the ratchet because it had less
slack. Confident in the fit, I began to pull the bar, putting
increasingly more pressure on it until I was closing in on my limit.
Success. The nut had relented to one of the most basic mechanical
principals. $25 later, I was headed back with a grin on my face.
I'd saved a bunch of cash and we could finish the project.
The starter installed and worked just fine, but we ran into a problem
when bleeding the clutch system. For some reason the pedal wouldn't
disengage the clutch fully or come all the way back up. Charlie
was convinced that the master cylinder was at fault, and that a new
one was needed. My elation at conquering the starter was dashed
as I realized that the master cylinder would cost at least as much as
the starter motor, and probably be harder to get.
On this sad note, I found a ride to take me back home, 40 miles north,
and left Charlie to think about the problem and resume work on Monday.
Monday, February 18th.
This particular Monday is the US Presidents Day, and I had the day off.
Thankfully I didn't need to find a ride to and from work, but home
offered very little to distract me from the state of the project.
I called Charlie at 9AM and was delighted to find out that he'd
resolved the clutch problem with a simple adjustment of the master cylinder
piston. The clutch was working perfectly, thought the key was
stuck in the ignition. The ignition switch is different on the
AT, to prevent the removal of the key unless the shifter is in park.
I was again elated, and agreed to call him back in a few hours to check
on the progress. At about 1PM, I called and Charlie told me to
come on down, that the car was ready to go.
As I arrived, he was just headed out to take it for a drive, but jumped
out and told me to take it for a spin. I immediately jumped in
and made myself familiar with the feel of the clutch and shifter.
The clutch was just about perfect. They hydraulics were taking
up just enough of the effort to make the engagement very smooth but
prompt. The shifter was a little messier. One missing item
was the spring that re-centers the shifter, so presently it tended to
flop around a bit. I shifted into a few gears back and forth to
feel the action, and then took off.
Immediately, the lightweight flywheel made its presence known.
I didn't kill the engine, but it did require a few more revs to
properly engage. Turning onto the street, I was immediately delighted
by the linear power all the way up to at least 5000 rpm; shift to second,
boost comes in quickly and into third. I immediately notice that
the speedometer isn't working, but I'm certain that I'm
well over 45MPH. Good grief.
Without my boost controller connected, and running about 6.5PSI of boost,
I'm giggling to myself and I've just confirmed that the money
and effort were all worth it. The car was easily as fast, if not
faster, than with nearly twice the boost. Dawdling around the
back streets in brief pulses of power, I quickly oriented myself with
the transmission and clutch. I again noticed how perfectly the
clutch engaged, how well it shifted gears, and how linear the power
was at such low boost.
Later I realized that the DIS-2's main power had been disconnected,
so reconnected it. The power again improved slightly and smoothed
out more, just like it'd noticed after installing it. The
speedometer simply needed to be re-seated and now works perfectly.
The key lock was easily defeated by shorting two of the wires originally
attached to the AT shifter to fool the car into thinking it was in neutral.
This apparently disables Cruise Control, but Alex installed a relay
that overcame this. I'll investigate further.
I still have to get the reverse lights to actuate properly, but it's
just a matter of finding out which wires on the old harness were responsible
for this, then wiring them up to the switch on the transmission.
I did not reinstall the TCU, and I'm not sure if that's going
to cause problems or not. I do have a significantly higher idle
than before, and it's slightly rougher aswell. Based on information
I got from Al on LegacyWorks, there's a single wire on the ECU
that tells it whether it should be and AT or MT ECU. I probably
just need to make sure I have the right wire, this B48 #20, snip it,
and see if that helps out.
A few other minor issues are the transmission filter and lines.
The cooler is integrated into the A/C condenser, so removing it is a
process in itself, but it would make excellent oil cooler, given the
proper plumbing. This could be a potential upgrade for those with
MT cars and no oil coolers. Swapping in the AT and A/C cooler
from an automatic puts the cooler in a prime position and eliminates
the hassle of installing a cooler elsewhere.
The center section of the console will need to be replaced if the stock
boot and assembly is to look any good at all. Finding the right
color might be the most daunting aspect of this task, as the early Legacies
came in a lot of colors. My interior is black, not a very common
color. I will also be adding a short shifter soon, with harder
bushings. By all measurements, the RS shifter should fit perfectly,
though I won't know until I try.
I will also replace the old transmission mount with at least a new stock
version, if not the Sti hardened version in the near future. I'd
like to do the same with the engine mounts, but that's a different
Well, that about wraps up the transmission swap. It's a job
that a shade-tree mechanic could perform, given the proper tools and
enough time. I was lucky enough to have an enthusiastic mechanic
with experience to help me out. The result is a very satisfying
car that is unique in many regards. Thanks to all those who helped
me get this done!