So after it’s been completed I wanted to share my saga on doing an XFE trans swap in my 2004 Ion. It wasn’t as easy as I first thought but hopefully this write up encourages others.

the transmission I chose was from a 2009 Chevrolet Cobalt XFE (RPO FY1). The prime motivation for this was to get the taller final drive ratio (3.63 instead of 3.84 in the Ion (RPO M86). I figured that being another Getrag F23 it would be a simple swap, and it wasn’t quite as planned.

first issue is that the front mount on the transmission was different. The top and the bottom bolt on my 2004 mount lined up and the middle one didn’t but GM and Getrag were generous enough to leave a block of aluminum in the proper place to drill and tap the case for the third bolt. We didn’t have metric drills or taps so my third hole is a slightly different size but that’s fine. The rear mount and the bell housing bolt holes are all correct though.

I chose to delete the roll pin in the shift linkage due to remembering breaking the one in the M86 transmission that came in the car. Required cutting out the roll pin (couldn’t drive it out with a 3lb hammer) and machining one from a hardened solid pin. This one(unlike the first solid pin that was made) was an interference fit, and required to be driven into the linkage with a hammer and grease. It massively tightens up shift feel.

The clutch was a major hassle for me, but only because I wasn’t prepared for it. The Ion clutch doesn’t work, it’s a different part number than the one for the 2009 Cobalt and as a result didn’t work. Do yourself a favor and buy a clutch kit for the 2009 Cobalt including the slave cylinder/throwout bearing. Also, be sure the place you get your transmission from includes the slave cylinder that is in the transmission, you’ll need it’s distribution block and a couple inches or clutch hose

the nipple on the end of the Ion clutch hose is different and won’t work with the Cobalt distribution block so you’ll need to take the couple inches of Cobalt clutch hose and cut out the steel nipple (take the opportunity to replace the o ring on the nipple. Also cut the Ion hose just behind it’s nipple. Heat the nylon hose with a heat gun or something and force it over the barb on the hose end of the Cobalt nipple. This is the only way to adapt the Ion master cylinder to work with the Cobalt slave cylinder. If you’re choosing now to upgrade to a lightweight flywheel, replace the flywheel bolts and if not the pressure plate bolts are safe to use again, just use blue Loctite on them when installing. Also, now wouldn’t be a bad time to change output shaft seals.

after all this adaptation the transmission can be installed just as the original one came out, and the clutch bled. The speed sensor plugs right in and works fine (the upshift light stopped working in my car I’m guessing bc the PCM didn’t recognize the new gear ratios) and the reverse sensor plugs in (had to change mine out though due to not functioning, double check yours). Everything else works just as intended, the car feels totally normal except for the difference in gearing. 0-60 runs can now be done with one gearchange instead of two and you turn less RPMs at highway speed.

i will report back with the differences in mileage once I get my alignment fixed, but things look promising!