Adjustments to the manual steering gear are not necessary during normal service. Adjustments are performed only as part of overhaul.Worm Bearing Preload
- Mount the gear in a vise.
- Using an inch lbs. torque wrench and spanner KV48101400, or its equivalent, rotate the worm shaft a few turns in each direction to settle the bearing and measure the existing preload.
- If preload is not 1.7-5.2 inch lbs. on 1989 models or 6.1-7.8 inch lbs. 1990-95 models loosen the locknut and turn the adjusting plug with the spanner, in a clockwise rotation ONLY. Never adjust preload by turning the adjusting plug counterclockwise. If preload cannot be obtained in this manner, rebuild the gear.
- Apply liquid sealer on the shaft threads and tighten the locknut to 181-231 ft. lbs. (245-314 Nm) on 1989 models, or 166-188 ft. lbs. (226-255 Nm) on 1990-95 models.
REMOVAL & INSTALLATION
See Figure 1
- Raise and support the truck on jackstands.
- Unbolt the wormshaft pinch bolt at the rubber coupling.
- Matchmark the pitman arm and sector shaft, and with the wheels in a straight ahead position, remove the pitman arm with a puller.
- Unbolt and remove the gear from the frame.
- Install the gear and tighten the bolts to 62-71 ft. lbs. (84-96 Nm).
- Press the pitman arm onto the sector shaft so that the marks are aligned and then tighten the nut to 94-108 ft. lbs. (127-147 Nm) on 1989 models, or 174-195 ft. lbs. (235-265 Nm) on 1990-95 models.
- Slide the worm shaft into the coupling pinch bolt and tighten the bolt to 17-22 ft. lbs. (24-29 Nm).
See Figure 2
If assembly does not meet specifications-replace the steering gear with a complete unit.
- Carefully clamp the steering gear in a vise.
- Set the worm gear in the straight-ahead position.
- Remove the sector shaft with its cover. Be careful not to damage the oil seal when pulling the shaft out. If the needle bearing require replacement, replace the gear housing.
- Loosen the adjusting plug locknut and remove the worm gear from the bearing. Don't let the ball nut run down to either end of the worm or else the ball guides will be damaged. Do not detach the ball nut or remove the needle bearings.
- Check the worm bearing preload.
- Using shims, adjust the sector shaft end-play so that it is 0.0004-0.0012 in. (0.01-0.03mm).
- Insert the sector shaft in position and set the worm gear in the straight-ahead position. Turn the adjusting screw until the sector shaft just touches the ball nut and then tighten the locknut. Lubricate the shaft and ball nut and then tighten the adjusting screw until worm gear preload is within specifications. Lock the locknut.
- Turn the worm gear several times to break in the worm bearing. Check that the steering gear preload is still OK.
- Coat a new oil seal with oil and press it into position.