Happens all of the time. It didn't engage fully and so you got that loud clunk noise. Leave it in 4 Full when you park. Don't switch when parked then switch it back again. You can stay 4 Full all the time.
Make sure the wheel is straight when shifting from 2-4 or 4-2 wd. Works better if you are driving. All you do is pull the lever to 4 Full-time and down on the lever until it is 2WD (4-Full light goes out and not showing 4 Part time either).
In the winter, not that Texas has to worry about it very often, but it would be best to leave it in 4 Full when parking and leaving it. You may find that you need it immediately in the morning.
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New KJ Gear -
Desert Armor Flak2004 Renegade Light Khaki - 4" JBA Lift - Rock Lizard Products: Komodo Dragon Rear Bumper, Prototype Winch-mount Front Bumper, Super Skink Sliders - All J's Super Tranny Skid II - 31" Firestone Destination AT's on Moab wheels - Cobra 75W CB w/ stock Antenna mod
[b]Retired, US Military