Tagging on also new here and wondering kind off the same thing here. I have a 197k 02 wrx auto and have a chance to buy a wrecked 04 5sp with 80k. Will the 04 drivetrain swap in without a ton off fab?

 

You wouldn't have to really do any fabrication, but the swap is a pain in the ass. You're going to need pedals, wiring, ECU, along with the clutch, transmission, shift linkage, center console, shifter itself, drive shaft.. probably more than than (I've never looked into it myself).


Whether or not a 6-speed would be worth it depends on several factors. Three of them being what do you plan on doing to the car mods wise, what you are going to use the car for, and what your budget is.

 

Why not just buy a manual transmission WRX if you haven't already bought one yet?

 

First off im new to the Subaru scene and im excited to learn and get into it, so just go easy on me! Im looking at getting a 2004 WRX, its a really nice car the only thing is i would like a manual but its an automatic. So i am curious as to how much a swap would be just for a 5 speed, or if it would be a better plan to go for an STI 6 speed. Also i would like to know what all i would need to do the swap. Any info you guys could give me would be greatly appreciated!!

I'm late but, I threw an 04 2.5rs trans in to my 04 wrx wagon (previously automatic). They both had the 4.11 final ratio so I didn't need to buy a differential. You'll need a new clutch/flywheel, I got a stage two 2.5rs clutch and an OEM WRX flywheel, seems to work fine right now, no slipping so far at stock power. I got the pedals and front half shafts as part of my deal, the front half shafts for the AT are female, you'll need male ones. Then you'll need a manual driveshaft because the automatic one is too short, maybe someone will trade you if they are doing an STi swap. For the 2004 model ECU, there is no manual identification pin. I learned this the hard way by cutting harness wires. I bought a MT ecu, but this works without it. In order to get the engine started, you'll either need to use the inhibitor switch attached to the auto trans; just take it off the old trans and dangle it in the engine bay and put it into neutral (improper), OR wire in an inhibitor relay that is attached to the clutch pedal switch(proper). There's a guy on YouTube (dirtcheapdaily) that walks through the mechanical installation, it is pretty straightforward and similar across models. The wiring is not standard across all models, however. There are wiring diagrams online for your model. I used one from a website called Busaru. The rev limit at 4k is the hurdle I am trying to get over now, but I believe it is because I didn't wire in my speed sensor yet, the automatic one has a 3 wire but the 2.5rs has a 2wire.