I just bought a 1996 f150 with 33s and notice sometimes the front end shakes really bad and I figured it was a wheel bearing or ball joints going out with the bigger tires. Any thoughts on what it could be? Thanks

 

could be any of those things. start with the simple stuff. get the tires balanced.

 

death wobble is what it sounds like. go out and give all the steering components a shake and see if any of the joints/tierods have any play in them. if so replace whatever it is. if not, then jack the truck up and try checking everything again. give your wheels a good shake to see if the wheel bearings or ball joints are bad. make sure you check your pitman arm to, because that was the problem on a buddies truck.

if everything seems tight, then do what the other guy said and go get your tires balanced

 

Could be tire balance but more than likely loose front end parts and worn out shock absorbers. The basic front end parts are upper and lower ball joints, tie rod ends, steering control arm, a arm bushings.
With the age of your truck, any or all of these parts may need repair/replacement.
If you don't know how to check these items, look em up on YouTube. They have videos for just about anything you need to do.