Mitsubishi Eclipse 5 speed Manual Transmission Swap

W5M33 designates the 2nd generation Eclipse 5 speed AWD Transmission. There are two variants, W5M33-2-NPZT used during 1995-1996 and W5M33-2-MUZT that are found in the 1997-1999 models. They're pretty much the same design but with a different front differential gear ratio. So it's important to use the matching year(95-96 or 97-99) transfer case for your Eclipse auto to 5speed swap.

This applies to both the Mitsubishi Eclipse GSX and DSM Eagle Talon Tsi AWD.

Front differential = Transfer case x Rear differential
• [Front differential] is the reduction ratio between the output shaft and the front axle
• [T-case x Rear-diff] is the reduction ratio between the output shaft and the rear axle
• The above equation must be met for the front and rear wheels to have the same turning rate. If you mix match your transmission and transfer case you'll be constantly putting load on your center diff spider gears and the viscous coupling.

An easy way to find out which year transfer case you have is to mark the transfer case output shaft and the input side coupler and see how many coupler revolutions it take to re-align the output shaft with the mark you made. The early year t-case needs 12 and the late year t-case needs 14 full revolution.

To distinguish the transmission, mark the front differential(where the front axle goes in) and the transmission output shaft. Turn the transmission input shaft until the front differential makes 5 revolutions and see if the output shaft re-aligns. If it does then you have a late year transmission.

Without any means to turn the transfer case coupler the only way to distinguish between the '95-'96 & '97-'99 transfer case is to open the cover and count the teeth. Fortunately the transmissions are stamped with their model name, but don't take anything for granted.

Remove the automatic brake pedal. You'll find there's a cable that attaches to the auto shifter. This is the shift-lock cable that prevents shifting from the Park position without pressing the brakes. Leave it there since the automatic shifter will be removed as well. The 5 speed manual brake pedal will be swapped in later on after installing the clutch pedal.

Remove the automatic shifter. You'll find there's another cable connected to the ignition key box. This is the interlock cable that prevents the key from turning into the "start" position when the Park/Neutral gear is not selected. You can think of it as an A/T version of the M/T interlock(clutch safety) switch. Unscrew the under cover on the key box and the cable just falls out with a few plastic pieces. The 5 speed manual shifter and cable uses the same mounting points and swaps right in.

Now that you have more space you can cut the firewall for the clutch master cylinder. This is the only cutting required from the entire process. If you look under the dash the sound deadener already has the shape cut into it. Just yank it off and you get a nice square opening. Looking at the firewall you'll see two holes already made on the inner layer from the factory, 1 for the master cylinder body and 1 for the lower master cylinder stud bolt. Cut through the outer layer with the appropriate hole saw and drill. After that you need to drill another hole for the upper stud bolt. Now you're 99% done. :)

Go under the hood and take a look at where the clutch reservoir would be. There are 2 round stickers on the firewall and if you take them off you'll find that you already have the clutch master cylinder reservoir bracket mounting points.

For the clutch hydraulics the OEM hard line is preferred. You can replace the fluid chamber and the short rubber hose with a $20 SS-braided line from RRE or other places. There's also a $80 full SS-line which replace the entire hydraulic lines. I mocked up my own because there were none at the time but won't go into details on the parts needed since they're readily available now.

Install the 5 speed clutch pedal. The Eclipse chassis already has the top 4 mounting points for the clutch pedal assembly. On the clutch pedal you have two switches. The left interlock switch is so that the car doesn't start without depressing the clutch. You won't need it so take it out or leave it unplugged since the auto doesn't have a harness. Cruise control will no longer work so the top cruise control switch will only be used to adjust the clutch height.

On the brake pedal there's the stop light switch. The 5 speed & automatic switch are different on how they thread in the brake pedal assembly. The auto switch is threaded like a bolt and the 5 speed stop light switch is a twist lock type. So you'll have to use the M/T switch and splice the wires since the connectors are also different.

Everything else is just a matter of swapping part A to B. If you were able to remove the auto parts then you can install the manual transmission parts with ease. The only thing worth mentioning is the shift cable install on the shifter side. The black bushing(red arrow) that goes on the Eclipse shift cable has a slit that should be at 12 or 6 o'clock position when installed. The white arrow in the picture shows the cable installed upside down. The larger surface area shown should be facing down.

After installing all the hardware you need to make one modification to the wiring to complete the 5 speed swap on your Eclipse. There's a 12-pin harness that plugs into the large park/neutral position switch on top of the auto trans. Since the A/T starter relay is active only when the gear is in Park/Neutral you need to jump 2 wires to mimic this condition. This activates the starter relay so it can send power to the starter motor when keyed to the "start" position. Reconnect the speedometer harness and you're done with the wiring. The rest of the harness, cooler and whatnots that were on the automatic transmission are not used anymore. Don't forget to remove the TCU under the dash next to the ECU. You can get access by removing the center console's driver side cover.

That's it. Go out and enjoy your new 5 speed Eclipse.