Q&A

 Master

I have come across this before on Honda and Acura where the brake master cylinder is replaced with a re-manufactured (or new) master cylinder. The pushrod length was incorrect and needed to be adjusted you may be able to test this by making a thicker gasket and putting it between the master cylinder and brake booster and see if the brakes still drag. If a thicker gasket works shorten the lenght of the pushrod. There is a company that independent auto repair shops "buy" their information from that offer a very reasonable service to do it yourselvers. You can get a one week subscription or year subscription very cheap. The information is year make and model specific repair procedures, service bulletins, component locations, wiring diagrams ect.... great quality information same as the professionals have ,much better than generic workshop manuals from parts stores, much cheaper than the factory manual try http://bit.ly/mitchell_repair_manuals_online
and get an online repair manual subscription.

 Rookie

my ford diesel f350 turbo is doing the same thing. I have the truck up on jacks. The front wheels turn freely until i start the engine. Autozone told me that the Vacuum pump can cause this so I replaced the pump. That did not fix the problem. I have discovered that if i disconnect the vacuum pump to the power booser the breaks unlock. The second I hook the vacuum line back up to the booster the wheels lock up again.