fwiw - I've always found traffic getting out of there to be not so bad - they've got so much experience with large crowds that they seem to manage it pretty well. Suggestion - look into one of the lots with a shuttle service; provided you don't mind a short ride to get there (heck, they start running a few hours before kickoff). From the quack site:
The Sports Shuttles provide the fastest, easiest, and least expensive transportation to Autzen Stadium on game days. The per game cost of a round trip is only $5.00, and is collected during pre-game boarding.
- LTD Eugene Station (11th & Olive)
- Lane County Fairgrounds (13th & Jackson)
- South Eugene High School (19th & Patterson)
- Valley River Center Parking Limited (Northwest parking lot)
- LTD River Road Station (River RD. & Beltline)
- RiverBend Annex (123 International Way - Southeast parking lot)
- LTD Springfield Station (355 South A St.)
- Thurston High School (333 59th St.)
Shuttle service to Autzen Stadium begins 3 hours before game time. Buses run every 10 to 20 minutes from 8 Park & Ride locations.Return trips from Autzen Stadium to Park & Ride locations are available ONLY during halftime and immediately following the game. Post-game departures will continue for 60 minutes after the game ends.Couple of those lots are close(r) to I5. And, think how much fun it'll be to be on a bus of crazed Duck nuts after we win.....
Others, I'm sure, will chime in.