I have a '93 suburban with bad motor. Can I put a '96 suburban motor in it.

Not really, The 93 runs off of OBD1 computer, and has a TBI set-up on it. The 96 runs off of OBDll computer, and is a vortec set-up, But you could do this by ordering a new intake manifold for your TBI, that will bolt on to vortec heads, and then set the motor up as it was originally. You would need to keep the drivers side exhaust manifold from the vortec.

Get the correct computer and wiring harness if you do the swap.