I attempted to put together a comprehensive set of notes for the XT site since there's a number of confusing options that some members have run into recently...2WD/4WD, turbo/nonturbo, air suspension, EJ or XT6. It could use some tweaking but i've already spent a TON of time that i probably don't have on it. I figured it could be useful here.
5 Lug Conversion Update
Read the “Variations” list at the bottom to see if any of the additional notes apply to you.
Front:
Control arms. XT6 control arms. XT6 and Impreza ball joints are identical. Subaru ball joint part # 21067GA050. If using an XT6 control arm, get the bolt that holds the arm to the vehicle. Some EA82's will require drilling the holes out bigger for the XT6 bolt. It is also possible to ream out the EA82 control arm to accept the XT6/Impreza ball joint.
Hubs: XT6 hubs or EJ hubs.
Sruts: XT6 struts or Impreza struts.
(You can mix and match XT6/EJ hubs and struts but the lower strut mount will require some tweaking if you don’t keep them the same.)
Axles: (Non-turbo see notes below) Turbo's Only: XT6 axles (or EA82 Turbo axles) for XT6 hubs. EJ axles for EJ hubs.
Tie Rods: XT6 or EJ tie rod ends - Subaru part #'s 31320GA190 RHS and 31320GA200 LHS. EA82 tie rods are a bit short but might work.
Brakes: XT6 calipers, brackets and rotors. 1999 Chevy Cavalier rotors are a much cheaper and easy to find equivalent. EJ brake notes below.
Rear:
XT6 rear hub assemblies (2WD notes below)
***NOTE*** For Impreza or EJ stuff mentioned above, hubs and struts should be from a 1993-2001 Impreza, including WRX up to 04 STi. Legacy hubs should work to up to 2004 at least, so the options are wide.
Variations: The following are various items that may affect the above list:
*** Non-turbo EA82’s***FWD Manual Impreza transmissions have an axle that should work - 1993 should do the trick. Non turbo EA82's have 23 spline inner axle joint (all XT6's, EJ's, and Turbo EA82's have 25 spline and there's no issue). The FWD manual impreza axle also has a 23 spline inner.
Another option is to build your own axle...swapping the inner non Turbo joint onto whatever axle you want to use - XT6, Turbo EA or EJ axle.
If you have an automatic transmission the axle stubs pop out, they just pull right out and pop back in. This being the case, you might be able to pull out your non-turbo splined stubby shafts and install turbo splined stubby shaft. Then just follow the directions above - using axles to match whatever hub you're using. This little trick isn't possible on manual trans as the stubs don't pull out.
***2WD*** If your EA82 is 2WD you will either need 2WD XT6 rear hubs or use entire 4WD XT6 rear hub assemblies (trailing arms and all)
***Air suspension note*** If you want to retain air suspension you will need XT6 front air struts or to see if Legacy front air struts will work. I am also told the Legacy air struts are too large for the EA82 strut towers as well, like the note above about EJ struts.
***Brake options*** For EJ brakes up front you will need to do a rear ebrake conversion as well via Nissan 200SX rear calipers. EJ brakes do not have the emergency brake up front, so converting to front EJ brakes essentially removes your emergency brake.
I am assuming that someone doing this swap knows they need NEW WHEELS!