SAFARI

34 REAR AXLE Fig. 70 Fig. 69 Check ring gear and pinion backlash at three equally spaced points with dial indicator. Fig. 69 Backlash tolerance is 0.13 to 0.20 mm. and should not vary more than 0.08 mm. between the three points checked. High backlash is corrected by moving the ring gear closer to the pinion. Low backlash is corrected by moving the ring gear away from the pinion. These corrections are made by switching shims from one side of the differential case to the other. If backlash is to specification CHECK the ring gear and pinion tooth contact pattern. INTERPRETING RING GEAR AND PINIONTOOTH PATTERN The toe of the gear tooth is the portion of the tooth surface at the end toward the center. The heel of the gear tooth is the portion of the tooth surface at the outer end. The top land of a gear foot is the surface of the top of the tooth. Fig. 70 The illustrations explain how contact pattern shift as gear location changes. When making pinion position changes, shims should be changed in steps of 0.05 mm minimum, until cor- rect pattern has been obtained. When a change in backlash is required backlash shims should be changed in the range of 1.5 times the amount of backlash required to bring the gears into specification. For example, if the backlash must be changed by .10 mm the shim pack should be ranged by .15 rnm as a starting point. The actual amount of backlash change obtained will vary, de- pending upon the ratio and gear size. Note: Making changes involves two variables. Ex- ample: if you have the backlash set correctly to specifications and you change the pinion position shim, you may have to readjust the backlash to the correct specification before checking the pattern. Refer to pattern inter- pretation.