Re: Expedition 4x4 Problem
electronic 4wd systems have what's known as the TCCM, or transfer case control module. It's the piece that controls the transfer case and tells it to switch modes. I'd get a proper diagnosis done, although I believe this is your problem, and get it replaced. You should be able to do it yourself with a good repair book (Haynes for instance). I'd also get the TCCM from a salvage yard, as it'll only be a fraction of what the dealer will charge you, and chances are you'll find a lower mileage doner vehicle!
'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!