Yes, you CAN tow your 4X4 on a dolly. After you load it on the dolly and tie it down, get under it and remove the rear driveshaft from the rear differential yoke. Put the nuts/bolts/clamps in a plastic bag, wrap the u-joint with tape to keep the bearing caps in place (black electricians tape works perfectly), and tie the shaft SECURELY to the bottom of the body.
then, when you want to use the vehicle, get under there and put the driveshaft back in place. tighten the fasteners firmly.
I used to have a Datsun 4X2 pickup that I had to do that with. It was no big deal back then. But, I was considerably younger. I wouldn't want to do it now!