The photodissociation spectroscopy and dynamics of the methoxy radical (A) over tilde((2)A(1)) <-- (X) over tilde(E-2) transition have been investigated using fast radical beam photofragment translational spectroscopy. The (A) over tilde state of both CH3O and CD3O is observed to predissociate via curve crossings with one or more repulsive electronic states. The photofragment yield spectrum consists of the C-O stretch progression and combination bands based on this mode. The major product channel is CH3 (CD3) + O, with a threshold 3775 cm(-1) above the zero-point level of the (A) over tilde state. The product translational energy distributions reveal nu(2) umbrella excitation in CH3 (CD3), yielding considerable insight into the dissociation dynamics for this channel. CD3O shows a mode-specific dynamical effect in which energy deposited in parent umbrella motion preferentially populates umbrella motion in the fragment. The product channels CH2 + OH (CD2 + OD) and D + CD2O are also observed, with evidence that the methylene fragment is predominantly in the excited (a) over tilde((1)A(1)) state.