2002 Chevy Trailblazer wheel bearing replacement.

Actually, they are hub bearings that come as a unit.

On 4WD vehicles, remove wheel center cap, if equipped, and the drive axle nut and washer
Raise and support the vehicle.
Remove or disconnect the following:

NOTE
Lay the hub and bearing on the wheel studs on the outboard side. This will avoid damaging the bearing seal.

Tire and wheel
Caliper, leaving the fluid lines connected
Brake rotor
Halfshaft from the hub and bearing on 4WD vehicles. Place a brass drift against the outer edge of the halfshaft to protect the shaft threads. Use a hammer to sharply strike the brass drift, but to do not remove the halfshaft at this time.
Wheel speed sensor
Wheel hub and bearing-to-steering knuckle bolts and hub and bearing

Splash shield from the steering knuckle
Seal from the hub and bearing

To install:
Install or connect the following:

Wheel hub and bearing seal
Splash shield to the steering knuckle, making sure it-s properly aligned
Hub and bearing to the steering knuckle, aligning the threaded holes
Hub and bearing bolts and tighten to 77 ft. Lbs. (105 Nm)
Wheel speed sensor. Tighten the bolt to 13 ft. Lbs. (18 Nm).
Rotor and brake caliper
Tire and wheel

Lower the vehicle
On 4WD vehicles, install the drive axle nut and tighten to 103 ft. Lbs. (140 Nm), then install the center cap.