RedZombie

I'm fairly new to this forum and not sure how to start a new thread. I have a 2002 4.0 L 4WD with 115K miles and automatic transmission. I just noticed it shifting late from first to second and kind of jerky a few weeks ago. All other gears shift fine. Then last week the O/D light began flashing as it shifts into 2nd gear. The code is p0733 (incorrect gear ratio). I'm worried that this is going to require a complete overhaul because both places I checked (small time mechanic and Ford dealer) throw out numbers like $2200. I've read stories online that would suggest that this is a common problem and there may be an easier more specific fix (solenoid, band, valve body gasket). I'm definitely not a mechanic, but my gut tells me that this could be a much easier/cheaper fix than what they tell me. The transmission was maintained and fluid level and color is good. I would appreciate any advice.