Disconnect the steering linkage from the pitman arm. Jack the truck up and put it on jackstands. Remove the wheels. Turn the wheels by hand. Do they move easily? They should. If not you have problems in the knuckles, probably ball joints.

If everything checks out, then Id start with the pump.

88 4R, 350 V8, R150 5 speed Sold <...uot; />
97 4R, stock, daily driver
98 Sienna, kid and dog hauler, wife's ride