You will not harm anything by driving with the hubs LOCKED.
True, based on the assumtion that all your front end universal joints are in good shape... I have a bad universal in my front drive shaft, and at highway speeds, it makes a nice vibration...
Lubing the hubs may work, try that first.
Removing them will definatly free up the front drive line... just seal up the hub, you might use some duct tape across the hub opening, should do the trick keeping dust/water out for a short while. And if the Defrost only situation with the heater/HVAC system is more than you want to deal with, you can disconnect and plug off the vac line at the vac pump on the right front wheel well... one line goes to the firewall for the HVAC sys, one goes down to the axle... as long as you make sure the one to the firewall is hooked up, you have normal HVAC controls... if you don't, you only get defrost, but the hot/cold knob still works. I had to do this on our Ex, the hubs have been switched out to standard ones, and the vac lines are shot going to the hubs, broken and such. I just took them out, plugged the line, and now the HVAC works fine, and the electric motor on the t-case still shifts ok.
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