99 Suburban Brakes/alternator

Please help! Relaced alternator yesterday and started fine and sounds good. When I started to drive it feels like the brakes are on. No lights are showing brakes or ABS. I took out the ABS fuse and it runs the same. Per my mechanic I tried disconnecting the battery for 30 seconds and then reconnecting. He thought the ABS were locked up. This didn't work. Any suggestions?

It appears to be a problem with the computer system. I disconected the battery for a few minutes. When I started it the 4 wheel drive light came on. I put it into 2 wheel drive and took it for a test run. The brakes stopped hanging up or actually it must have been in 4 wheel drive(yeah!).

You will have to jack-up the vehicle and actually see if the brakes are locked up.

Then we will go from there...