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Old 06-02-2012, 02:10 PM   #1
Scooby Newbie
Member#: 194453
Join Date: Nov 2008
Location: central NH
2001 Legacy 2.5 GT
Winestone Pearl

Default 2001 Legacy 4EAT to 5MT manual swap

So I will try to make this as detailed as possible... I swapped my 2001 Legacy GT from the 4EAT to a 5 speed manual. The transmission I got was from a 2002 Impreza 2.5 TS from Vermont that had been hit in the side and totaled. I ripped the trans and pedal assembly out myself just to see how it came apart so it would be easier putting back together. This thing was RUSTY! Amazing how much a car can rust in 10 years. Anyway it took me pretty much the whole morning and into the early afternoon to take the trans, pedal assy, driveshaft, shifter assy, and master cylinder out. The rear differential was WAY too rusty to take out. I jumped on the cheater bar on those bolts and it would not budge. Fortunately, I grabbed a rear 3.90 rear diff from a legacy in the junkyard a few months back and discovered that the ratios were the same. That was pretty much all I needed from the donor car. While my Legacy was off the road, I figured I would take care of a few things. The timing belt was due in a couple thousand miles, so while the engine was out, it would have been stupid not to. I bought a set of Bilsteins from Japan. Also, I decided to rust proof a bunch of things seeing as how I live in New Hampshire ...

Here is the list of all of the parts I needed and purchased and how much it ruined my bank account:

  • -$400 5-speed manual Transmission, Pedal Assembly, Rear Differential, Master/slave cylinder, clutch lines, Transmission crossmember
  • - 330 Bilstein shocks and struts from Japan (used, with shipping)
  • - 15 Shifter linkages- these are model specific. The ones from the Impreza would not fit in the Legacy body. Had a hell of a time finding some that hadn't been hacked off by the junkyard workers that rip out the engines and transmissions. Thankfully they sold them cheap they run $300+ at the dealer.
  • - 25 driveshaft- I originally was planning to swap my 98 wagon, so I got a driveshaft from the 2nd generation legacy. Turns out it fits on the 3rd gen too.
  • - 286 Brand new clutch and lightweight flywheel kit. Flywheel weighs 12.5 lbs
  • - 196 Timing belt water pump kit including all the pulleys and tensioner
  • - 26 thermostat/seal
  • - 8 exhaust manifold gaskets
  • - 8 donut gasket between cat and midpipe
  • - 17 trans and diff fluid. Got cheap stuff at first to make sure everything worked. Will put higher quality fluid in in a few thousand miles
  • - 63 POR15- This is very high quality rust preventative paint. Bought a gallon with my landlord and split the cost.

I did not need cv axles, fortunately they were all the same length. One for the rear was a different part number however. I think because the manuals have power split 50/50 front to rear and the automatics do not, the rear axle in the manual may have a higher torque/hp rating, not sure just a guess. It still fits right into the diff.

Total I spent just under $1,400. I highly recommend getting new engine mounts and trans mount and shifter bushings (as long as it needs them, while everything is apart). I made the mistake of not doing so, so my trans mount is very deteriorated along with the rear bushing that holds in the shifter assy.

Day 1:

Most of the day I spend clearing the garage and preparing everything. Got the car up on jack stands. Took out the old shocks and struts. I spent ~$800 on a whole set of new KYBs with H&R springs. I loved the way it sat, but the ride was far too stiff. That was 20k miles ago, and figured I'd change them while it was apart. Which is why I bought the Bilsteins, so I could still get some money for my old shocks and springs.

Took off the whole exhaust and the shield just below the drivedshaft.

I also swapped out the rear differential. Unbolted the driveshaft from the diff. Got the 2 bolts on the back using a very long cheater bar and dropped the whole thing with the small frame holding it in. I did not have to disassemble anything else in the rear suspension. I dropped the diff with a jack, slowly step by step while prying out the cv axles AFTER draining the fluid in the diff. I cleaned off the diff that had been sitting in the basement and jacked it in while inserting the axles. That was enough for one day....

Day 2:

Spend the day taking apart all the plastic bits in the wheel wells along with the fuel filler neck (notorious rust spot). Cleaned off all of the dirt and grime on the underside and in the wheel wells. Put one coat of the POR15 paint on the rear wheel wells. This was very time consuming. Day 2 over.

Day 3 & 4:

Drained the coolant, took out the radiator and eventually got everything taken off the engine so that it was ready to be pulled. Unhooked the auto shifter assy. Drained the trans fluid and removed the driveshaft. Got the left axle bolt free and took out that axle so that the trans would come out a little more freely. Got the engine hoist and lifted the engine and trans as one unit while taking out the other cv axle. This was quite the pain in the arse. The 4EAT is so massive it just barely fit through the space between the firewall and the front subframe. The engine had to go up more and the rear of the trans had to come down. After quite a bit of wrestling and rocking it finally came free. Had to keep a drain pan under the back of the trans, fluid will pour out...

Day 5:

Cleaned and prepped more of the underside. Pretty much spend the whole day painting. Did two coats on the underside and the wheel wells. Also disassembled the auto shifter assy inside.

Started tackling the pedal assy as well. This took a lot of wrestling. Getting the auto brake out is not hard, but getting the other one in was very difficult. The brake and clutch are on the same assembly, the gas pedal is separate and is the same part on the auto and the manual, although it does need to be unbolted to fit the clutch/brake assy behind it. I also realized that the brake light switch is different on the manual, but that was just a matter of swapping the one over from the auto brake pedal. I also popped out the rubber plug that goes in the holes where the master cylinder comes through the firewall.

Day 6:

Today was a very busy day. My friends came up from PA and helped tremendously. First, we got the bolts off of the torque converter. These bolts are ridiculously soft and very easy to round off. They are also fairly hard to get to. It is wise to remove the bolts holding the torque converter to the flex plate first to assure the TC stays on the transmission. I learned that the hard way on my other subaru and spent over an hour trying to fit the TC back into its place in the trans. After my landlord got those bolts free, the engine and trans could then be separated.

After they were separated, we then took the flex plate off. The bolts that hold on the flywheel (where the flex pate bolts to on the auto) are longer than the bolts that hold on the flex plate. I bought an old 2.2 liter engine a few months back that had a clutch on it, so I disassembled that and used those bolts to hold on my flywheel. The new clutch was assembled and the 5MT was bolted back to the engine. Also replaced the timing belt, water pump, tenisioner, and idler pulleys while the engine was out of the car. I had never done it before so I was very hesitant, but my landlord helped me out, yet again, and finished all of that.

After i knew all of the POR15 rust paint was dry and solid, I put in the bilsteins and got most of the suspension back together. In the mean time my buddy took all the good bits of all of the shifter assemblies that I got and made one good one. Again, I should have bought new bushings while it was apart...

Amazingly we had the engine and trans back in the car by the end of the 6th day. There was still a lot of hooking up to do but it was in the car.

Day 7:

Got everything on the engine where it needs to be. Attached the shifter assy in the car. The bushing in the back that holds the shifter in place went missing for several hours.... Almost put a stop to the project. Finally it turned up. On the underside of the body behind the space where the shifter goes through were two plastic plugs that covered threaded bolt holes. I popped those out and found 2 bolts that threaded into there (bonus bolts from other projects). You can kind of see the rusty bracket on the bottom of the pic. Thats on the back side.

The transmission subframe pretty much just bolted in. Although at first we did not have all of the pieces. I got a subframe from a junkyard thinking that it may have been different on the legacy and impreza. So I thought I had the subframe bolted in but there's a piece in the front that spans almost the width between the control arms. There was another set of plastic plugs that covered threads in the body right next to the bolt that holds the control arm onto the body. I popped those out and used the subframe that I originally got from the impreza. Again I found two big bolts from other projects that fit those holes. Turns out the one out of the legacy that I got from the junkyard had that piece missing. The impreza and the legacy one are interchangeable. I used the impreza one reluctantly, it is very rusty. Will probably need to find one in better shape in the future. I do not have a picture of it...

As for the wiring on the starter, we basically hotwired it. Ran a wire directly from the ignition to the starter. This got around the start interrupt that does not allow the car to start if its in R or D. So we heard it run briefly which was very nice to hear. Then I turned it off and the key would not come out of the ignition. On the automatics it holds the key in unless its in P. We took off the cover under the ignition and found the little solenoid that moves back to let the key out. My landlord plugged that pin that sticks down with the end of a zip tie to stop it from locking.

By the end of the day it was ready to be put on its wheels and tested And she moved! Backed out of the garage and took her for a test drive. The first noise we noticed was the lower boot on the shift linkage rubbing against the driveshaft. I just poked some more holes in the boot to stretch it out of the way. Mechanically so far everything is working smoothly. What a relief.

Now there's the issue of the 8 Check Engine Light codes. And the speedometer. I did not want to drive it much without the speedo working. Didnt want to rack up too many unknown miles. After a LOT of trial and error with the speedo I finally got it to work. The automatic has 3 Vehicle Speed Sensors, one for the torque converter, one front and one rear sensors. I think it has those two because the auto splits power 50/50 when the front wheels slip.

This is the link I used for the ECM pinout:


With the 3 pins on the ECU:


for the VSS there are 3 wires coming out of the trans. One is power going to the sensor, one is ground and the other is the signal. Black and Red is the ground, just found a ground on the firewall that was close. As of right now its still in 'test mode...' I have wires looped around the outside of the car to test it. The VSS needs 5 volts to power it. I found that by sliding a wire in to one of the pins on the ECU. I found out the one that powers the fuel tank pressure sensor power supply has 5 volts after looking at a pinout of the ECU (B136 pin 15). So I found some spare wire and tested all my voltage with a multimeter. As for the signal, I used B135 pin 24 and hooked up the wire with both ends of the original wire (goes to the speedo and the ECU). Speedo works! still need to find 5 volts under the hood and find the signal wire that goes through the firewall, but at least I know which wires go where...

After I got the speedometer working I took it to work the next day. I hadn't driven it too much with no speedo. Took it to work and back once before and drove around town a little bit, so I drove it maybe 60 or 70 miles. On the way home from work it started holding the throttle. If I was in gear it would hold the throttle a little bit, not enough to make it accelerate but definitely noticeable. It would hold it for maybe 6 or 8 seconds then fuel cut. It forced me to ride the clutch when upshifting. very very annoying. I had the battery disconnected all night and tried again in the morning. This time it idles at 3k rpm. Just hangs there. So far my CELs are a bunch of trans error codes and the heated o2 sensor circuit. Its pouring all day so it will be a while until I can figure this out.

I grounded the pin that supposedly tells the computer that the ECU that the car is manual. B135 pin 4 pink wire. That did not seem to do anything though. it still gives me AT error codes. I grabbed a computer from an 00 legacy 5MT and for some reason it will not run with that computer. It cranks and cranks then suddenly stops. but will not actually start. tried reading codes on that computer but it does not throw any. Im wondering if it has something to do with MAP sensor vs. MAF. Mine is a MAP but I know that changed from year to year.

I dont know what to do at this point. Once it dries up outside Ill check all of my o2 sensor wires and plugs. make sure its all correct. Other that that Im pretty stumped. If anyone has any input it would be greatly appreciated. Feel free to ask me any questions if anything is not clear. Im not the best at explaining things....
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