Land Rover Repair: brakes lock up, release brakes, brake drum

Question
Hi. My 2001 Disco II has problem with brakes locking up.  I replaced the transmission and transfer case. When it shifts out of low gear the brakes lock up.  When you ease up on the gas briefly the brakes release.  Brakes lock up again when you shift out of low gear.  What's my problem?

Answer
I have never seen a Rover do what you say.  Is the traction control activating, so you hear it buzzing when the brakes apply?  How do you know the regular brakes are the problem?   If I were to guess I'd say its much more likely there is an assembly error and the parking brake drum is grabbing.