05flhtcse, you are about 100% right as I have a 2009 R/T now sitting in my garage with the 28J package and what I ordered extra was the Electronics Conveinence Group , the Light Gray inserts( no Charge), the spare tire, 20" chrome wheels, and sound groupII which was extra $ but it came with 276 watts of power and 6 speakers instead of 4 . The 28J page was called the "Customer Conveinence Group ". This info is direct from the factory window sticker that came with the car at delivery. Just to clarify much of what you said, Fat Cat[sm=gears.gif]
ORIGINAL: 05flhtcse
Things that J has and F doesn't. Auto head lamp capability, power mirrors, electronic vehicle information center capability, homelink capability, keyless go, illuminated cup holder and door pull capability, rearview mirror auto dimming capability, steering wheel controls capability, temperature display capability, light gray leather seat inserts, heated seats, security alarm capability, tire pressure alarm capability, electronic convenience group option, sound group II option.
On the other hand, J package can not have the cloth seat option.
As you can see, the J package lets you choose more options but you don't necessarily get them free, the F package limits your choices.
Probably not the best explanation but gives you an idea. I took these differences from a 2009 sales brochure.