Spicer Single Drive Axles Service Manual: 34DS, 34RS, 38DS, 38RS, DS340, RS340, DS380, RS380, DS400, RS400, DS3 - Manual (Page 34)

Adjustments
31
Differential Bearing Preload and Ring Gear Backlash Adjustment
Special Instructions
Correct differential bearing preload insures proper location of these bearings under load and helps position the ring gear for proper
gear tooth contact.
Procedure - Adjust Diff. Bearing Preload
1. Lubricate differential bearings.
When installing bearing caps and adjuster, ex-
ert care not to cross threads.
2. Install adjusters and bearing caps. Tighten bearing cap
screws finger-tight. If this is difficult, use a hand wrench.
Note: Ring gear position for rear axle is illustrated.
3. Loosen the bearing adjuster on the same side as the ring
gear teeth until its first thread is visible.
4. Tighten the bearing adjuster on the back-face side of the
ring gear until there is no backlash.
This can be tested by facing the ring gear teeth and push-
ing the gear away from the body while gently rocking the
gear from side to side. There should be no free movement.
Rotate the ring gear and check for any point where the
gear may bind. If such a point exists, loosen and re-tight-
en the back side adjuster. Make all further adjustments
from the point of tightest mesh.
5. At teeth side of ring gear, tighten adjuster until it contacts
the bearing cup. Continue tightening adjuster two or three
notches and this will preload bearings and provide back-
lash.
6. Measure backlash with a dial indicator.
USED GEARING — Reset to backlash recorded before dis-
assembly.
NEW GEARING — Backlash should be between 0.006”
and 0.016”.
If backlash is incorrect, proceed as described below to re-
adjust.
Procedure - Adjust Ring Gear Backlash
1. To add backlash: Loosen the adjuster on the teeth side of
the ring gear several notches. Loosen the opposite adjust-
er one notch. Return to adjuster on teeth side of the ring
gear and tighten adjuster until it contacts the bearing cup.
Continue tightening the same adjuster 2 or 3 notches. Re-
check backlash.
2. To remove backlash: Loosen the adjuster on the teeth side
of the ring gear several notches. Tighten the opposite ad-
juster one notch. Return to adjuster on teeth side of ring
gear and tighten adjuster until it contacts the bearing cup.
Continue tightening the same adjuster 2 or 3 notches. Re-
check backlash.
3. Moving adjuster one notch is the movement of the lead
edge of one adjuster lug to the lead edge of the next lug
past a preselected point.
IMPORTANT
One
Notch
Lugs
Lugs
One
notch