lowfareair

I completely forgot that I started a list about six months ago and never finished it. Here's what I have so far. Apologies if it is a little out of date, let me know if you have any updates for it (including actual class letters for some of the rarer classes):

Economy (A)
-Chevy Aveo
-Hyundai Accent
-Kia Rio

Compact (B)
Common:
-Chevy Cobalt
-Ford Focus
-Nissan Versa
-Toyota Yaris
Rare:
-Nissan Cube

Intermediate (C)
Common:
-Toyota Corolla
-Mazda3
-Mazda5
-Nissan Sentra
Rare:
-Honda Civic
-Toyota Matrix
-Chevrolet HHR

Standard (D)
-Chrysler Sebring
-Ford Fusion
-Mercury Mariner

Full-size (F)
Common:
-Chevy Impala
-Chevy Malibu
-Ford Taurus
-Toyota Camry
Rare:
-Honda Accord
-Mazda6

Premium (PCAR)
-Mercury Grand Marquis
-Nissan Maxima

Premier Premium(UDAR)
-Toyota Avalon

Luxury (H)
-Lincoln Towncar
-Lincoln MKZ
-Cadillac DTS

Midsize SUV (Q4)
-Chevy Equinox
-Ford Escape
-Nissan Rogue
-Pontiac Torrent
-Subaru Forester
-Subaru Legacy
-Subaru Outback
-Toyota Rav4

Standard SUV (SFAR)
-Ford Explorer
-Nissan Xterra
-Toyota Highlander

7 Passenger Standard SUV (FRAR)
-Chevy Traverse
-GMC Acadia
-Mazda CX-9

Large SUV (FFAR)
-Chevy Tahoe
-GMC Yukon

Premium Extra Capacity SUV (PFAR)
-GMC Yukon XL
-Chevy Suburban

Crossover (SRAR)
-Saturn Vue

Minivan (MVAR)
-Chrysler Town & Country
-Dodge Grand Caravan
-Kia Sedona

Convertible (STAR)
-Chrysler Sebring
-Ford Mustang

Pickup Truck (SPAR)
-Ford F-150

12 Passenger Fullsize Van (FVAR)
-Ford Super Clubwagon

Adrenaline Collection
-Chevy Camaro
-Chevy Corvette
-Ford Mustang
-Ford Mustang Convertible
-Jeep Wrangler

Green Collection
-Ford Fusion
-Nissan Altima Hybrid
-smart fortwo
-Toyota Camry
-Toyota Camry Hybrid
-Toyota Corolla
-Toyota Prius

Prestige Collection
-Cadillac Escalade
-Cadillac SRX
-Infiniti FX35
-Infiniti G37
-Infiniti M35/M37
-Infiniti QX56
-Lincoln Navigator
-Mercedes C class
-Mercedes E class
-Mercedes GLK350
-Volvo C70
-Volvo S80

Unknown class
-Subaru Impreza