Mitsubishi Repair: 1992 2.4L motor, mitsubishi expo lrv, plymouth colt

Question
I have a 92 eagle summit wagon that uses the 2.4L mitsubishi motor and 5 speed tranny.  220,000 miles on the motor now - runs fine, just uses a quart of oil every 100 miles.  Would replacing valve stem seals significantly reduce the oil consumption?  I'm also thinking of replacing the whole motor and tranny (bad 1st and 2nd synchros) with a motor and tranny from another vehicle with less miles.  Do you know what year(s) motor will work in this vehicle? Does it have to be another 1992?
Thanks.

Answer
Mark,
Leaky valve seals and valve guides can cause quite a large amount of oil consumption.  Having to add a quart every 100 miles is a huge oil consumption.  I would have almost guessed you were leaking oil as well.  But if you're not leaking oil on the ground, I'd guess your piston rings are significantly worn and allowing a lot oil to pass through the combustion chamber.  Sounds like you would need a major engine overhaul.  But since you're planning on replacing the engine and transmission, that may be the best route.

Other years and models that may be equivalent to your '92 Summit wagon are other Summit wagons from '92-'96.  Also, the Mitsubishi Expo LRV and the Plymouth Colt Vista are also nearly identical.  But do some additional research before you purchase other years or models.  Though the engine and transmission may be identical, wiring harnesses and the engine control units may be slightly different.  Also, be sure to note whether the parts are either coming from an AWD or FWD Summit wagon.  If you currently have an AWD wagon, you'll probably want to replace the transfer case and perhaps the rear differential as well.
Good luck!