Rear Axle: Models FA and FB
Rear Axle: Models FA and FB
10-81E-14
CHAPTER                                   10
REAR AXLE
Models FA and FB
  TROUBLESHOOTING ...............................................................10 - 2
                                                                                                          10
  SPECIAL TOOL .........................................................................10 - 3
         DISASSEMBLY ................................................................10 - 5
         INSPECTION ....................................................................10 - 8
         ASSEMBLY AND DISASSEMBLY ...................................10 - 11
TROUBLESHOOTING
                 Gear system
                 ● Inadequate backlash on ring gear
                   and pinion gear ............................................. Adjust backlash
                 ● Worn thrust washers ..................................... Replace
                 ● Worn differential spider ................................. Replace
                 ● Worn or damaged ring gear and pinion ........ Replace
                 ● Worn or damaged differential side gears
                   and pinions .................................................... Replace
                 ● Loose ring gear tightening bolts .................... Tighten bolts
                 ● Inadequate tooth contact of ring gear and
                   pinion gear .................................................... Replace or adjust tooth contact
                 ● Worn pinion spIine ........................................ Replace
                                          SPECIAL TOOL
Prior to starting a rear axle overhaul, it is necessary to have those special tools.
                                       09849 - 1601
                                                                  HANDLE
                                       09849 - 2001
                                                           1
                                                                2
                                                                      3
                                     9                                                 4
                                              10
                                                                                            3
                                                                                                 5
                                                                     19                              6
                                                                                                         7
                                                                                                             1
                                                                      14                                         8
                                                                                  11
                                                                            15
                                                                                       12
                                                                           16               13
                                                     16
                                                    15
                                                           17
                                         18
                                                                                                                     SM10-543A
                    DISASSEMBLY
                    1.   REMOVAL OF WHEELS
         SM10-488
Fig. 2
                         1.   Using a socket wrench, loosen the rear wheel nuts
                              a little.
                                               WARNING
                          ● When jacking up the rear axle, place a jack cor-
                            rectly to the axle, and then lift up the axle.
                          ● Do not get under the vehicle when it is supported
                            by a jack only. It is very dangerous as the jack
         SM10-346
                            might slip.
Fig. 4
                          ● Use safety stands which have sufficient strength
                            and stability to support the vehicle whenever you
                            need to work under it.
                 SM10-524
Fig. 6
                                                      WARNING
                                  ● Do not work on brake drum while it is still hot,
                                    this can result in personal injury.
                                  ● The drums are heavy. The rear drum weighs 30
                                    kg (66 Ib). Be careful not to drop them.
                                  ● To assure safety, do this operation with more
                                    than two persons.
                 SM10-546
Fig. 7
                                 3.   Remove the oil seal, and then loosen the bolts and
                                      remove the lock plate.
                 SM10-547
Fig. 8
                                 4.   Remove the taper roller bearing lock nut using a
                                      special tool, and then remove the lock washer.
                 SM10-548
Fig. 9
                       1 page 1
                     Models FA and FB                             REAR AXLE 10-7
          SM10-349
Fig. 11
                        7. Remove the ABS wheel sensor.
                           After removing the harness connector for the ABS
                           wheel sensor and the cable clip, remove the ABS
                           wheel sensor with its holder.
                        NOTE: Subjecting the wheel sensor to a strong
                               shock can cause internal damage. Do not
                               strike the wheel sensor with a hammer or
                               bump it against other components.
Fig. 12
                        8.   Remove the wheel brake.
                             Disconnect the brake line, loosen the attaching bolt,
                             and remove the wheel brake assembly from the axle
                             housing.
          SM10-500
Fig. 13
                                 1 page 1
10-8 REAR AXLE               Models FA and FB
                            INSPECTION
                            1.   INSPECTION OF THE WHEEL HUB
                                 1. Inspect the taper roller bearing with race for burns
                                     or pitting, and replace it if such defects are found.
                 SM10-501
Fig. 14
                                 2.   Inspect the taper roller bearing race for burns, cracks,
                                      or brinelling on the raceways, and replace it if such
                                      defects are seen.
                 SM10-550
Fig. 15
                                 3.   Replacement of taper roller bearing race.
                                 a.   Remove the taper roller bearing race from the hub
                                      bore.
                 SM10-551
Fig. 16
                                 b.   Install the new taper roller bearing race in the hub
                                      bore.
                 SM10-552
Fig. 17
                                 4.   Inspect the hub bolts.
                                      Replace the bolts if the threads of the bolts are worn
                                      or damaged.
                 SM10-553
Fig. 18
                                  1 page 1
                                Models FA and FB                              REAR AXLE 10-9
                     SM10-506
Fig. 19
                                   b.   Install the new hub bolts in place on the wheel hub.
          SM10-507   SM10-508
                                   Tightening Torque : 4,000 - 4,800 kg·cm
Fig. 20
                                                       (290 - 347 lb·ft)
                                                   A : Stake
                     SM10-509
Fig. 21
                                   7.   Inspect the axle shaft spline for wear or damage.
                                        If the spline is excessively worn or damaged, replace
                                        the shaft.
                     SM10-510
Fig. 22
                                        1 page 1
10-10 REAR AXLE                       Models FA and FB
                           SM10-511
Fig. 23
                                         9.   Sensor ring
                                         •    Visually inspect for any damage or deformation of
                                              the sensor ring or protrusion from the wheel hub, etc.
                                         •    If there is any damage or deformation, replace the
                                              sensor ring.
                                         •    If the sensor ring is protruding from the wheel hub,
                                              push it in using a press board.
Fig. 24
                                         a. Removal of the sensor ring
                                            Uniformly tap on the periphery of the sensor ring
                                            using a screw driver or the like and remove it slowly.
                                         NOTE: When tapping and removing the sensor ring,
                                                be careful not to damage the wheel hub.
Fig. 25
      PRESS BOARD
                                         b. Installation of the sensor ring
                      SENSOR RING
                                         1) Set the sensor ring in the wheel hub and uniformly
                    GAP
                                            push equally using a press board.
                                         NOTE: Warming up the sensor ring with warm water
                                                before pushing it in enables the procedure
                                                to be carried out smoothly. Never use a gas
                     ADHESION
                                                burner. Doing so can cause the sensor ring
                                                to be deformed.
                                         2)  After pushing it in, check the axle direction wobble
Fig. 26
                                             of the sensor ring.
                                         Standard range: Under 0.2 mm (0.0079 in.)
Fig. 27
                          1 page 1
                      Models FA and FB                               REAR AXLE 10-11
          SM10-512
Fig. 28
                          2. Install the wheel brake assembly to the axle-hous-
                             ing.
                          NOTE: ● Refer to CHAPTER 13, SERVICE BRAKE.
                                  ● The installation of the ABS wheel sensor
                                      is not proceeded.
                                              WARNING
                           When hammering, a metal tip may fly off on impact.
                           Wear safety glasses to protect your eyes.
          SM10-513
                          NOTE: This procedure must be performed after the
Fig. 30
                                ABS wheel sensor has been removed.
                          5.  Install the ABS wheel sensor.
                              After applying a thin film of chassis grease to the
                              wheel sensor body, press the wheel sensor into the
                              clamp bushing (holder) until the tip of the wheel sen-
                              sor and the side surface of the holder become flat
                              and install the holder on the base portion of the axle
                              tube and tighten with the specified torque.
                          Tightening torque: 351 - 527 kg.cm (26 - 38 lb·ft)
Fig. 31
                          NOTE: ● The bolts should be tightened by hand.
                                  Never use an impact wrench.
                                ● In this condition, the wheel sensor is still
                                  temporarily installed and should be fi-
                                  nally installed after the pre-load adjust-
                                  ment of the wheel hub assembly.
                                   1 page 1
10-12 REAR AXLE                  Models FA and FB
                      SM10-554
Fig. 32
                                    5.   Install the wheel hub and taper roller bearing (outer)
                                         on the axle housing.
                                         Using a pipe, as shown in Fig. 33, makes the work
                                         easier.
                                                       WARNING
                                     ● The wheel hub assembly is heavy. The wheel hub
                                       assembly weighs 20 kg (44 Ib). Be careful not
                      SM10-555         to drop it.
Fig. 33                              ● To assure safety, do this operation with more
                                       than two persons.
                                     ● When hammering, a metal tip may fly off on im-
                                       pact. Wear safety glasses to protect your eyes.
                      SM10-556
Fig. 34
                                    7.   Loosen the lock nut by 1/4 to 1/3 turn using a spe-
                                         cial tool. Then strike the wheel hub with a copper
                                         hammer.
                                                        WARNING
                                     When striking, a metal tip may fly off on impact.
                                     Wear safety glasses to protect your eyes.
          SM-10-548   SM10-557
Fig. 35
                       1 page 1
                     Models FA and FB                              REAR AXLE 10-13
          SM10-598
Fig. 36
                        9.   Apply the lock plate and align it with the small screw
                             hole of the nut. If the hole does not align, turn over
                             the plate. If alignment is still unattainable, turn the
                             lock nut further within the limits of hub turning torque
                             of 40 - 60 kg·cm (2.9 - 4.3 lb·ft)
          SM10-558
Fig. 37
                        10. Install the oil seal on the wheel hub.
          SM10-559
Fig. 38
                        11. Install the axle shaft in the wheel hub and tighten
                            the set bolts to the specified torque.
          SM10-560
Fig. 39
                                        1 page 1
10-14 REAR AXLE                       Models FA and FB
Fig. 40
                       WHEEL
          MAKE CONTACT SENSOR
    SENSOR
    RING
HUB
                            CLAMP
                            BUSHING
Fig. 41
                                         12. Install the brake drum on the wheel hub and tighten
                                             the drum set bolts.
                                                             WARNING
                                          ● The drums are heavy. The rear drum weighs 30
                                            kg (66 Ib). Be careful not to drop them.
                                          ● To assure safety, do this operation with more
Fig. 42                                     than two persons.
                       1 page 1
                     Models FA and FB                            REAR AXLE 10-15
                                              WARNING
                         The specified torque should be observed for tight-
                         ening wheel nuts. Improperly torqued wheel nuts
                         can cause the wheel to come off while driving. This
                         can result in personal injury and/or property dam-
                         age due to loss of vehicle control.
                         When the vehicle, wheels or wheel nuts are new,
                         the wheel nuts should be checked and tightened to
                         specified torque at 100, 500, and 1,000 miles since
                         they are not well seated. The tightening torque
                         should be checked with a proper torque wrench.
                                        DIFFERENTIAL CARRIER
                                              (HINO SH13-2 series)
                                             13
                                                  5
                                                      14        15
                                    7                                                                21
                               6                                      16             18
                                                                           17
                                                                                          19                       22
                           5
                       4                                                                  20
                   3
               2
         1
24
                                        10                                                 23   15
                                                                                12                        5
                                    9                      11                                                 13
                       5
                                                                                                               SM10-492A
               8
Fig. 1
                                   1 page 1
10-18 REAR AXLE                Models FA and FB
                              REMOVAL
                              1.   REMOVAL OF DIFFERENTIAL CARRIER
                   SM10-488
Fig. 2
                                   1.   Disconnect the propeller shaft from the flange at the
                                        differential carrier.
                  SM10-595A
Fig. 3
                                   2.   Remove the filler and the drain plug to drain the gear
                                        oil from the axle housing.
                                                         WARNING
                                    Do not work on differential carrier while it is still
                                    hot.
                                    This can result in personal injury.
                   SM10-422
Fig. 4
                                   3.   Remove the bolts, and then pull the axle shafts out.
                   SM10-489
Fig. 5
                                   4.   Use a jack to dismount the differential carrier assem-
                                        bly from the axle housing.
                                                         WARNING
                                    ● When loosening the tightening bolts of the dif-
                                      ferential carrier, do not place yourself under the
                                      differential carrier.
                                    ● Be sure to apply a support before dismounting
                  SM10-565A
                                      the differential carrier assembly.
Fig. 6
                           1 page 1
                       Models FA and FB                              REAR AXLE 10-19
                      DISASSEMBLY
                      1.   DISASSEMBLY OF THE DIFFERENTIAL CARRIER
                           1. Mount the differential carrier assembly on a work
                               stand.
          SM10-425B
Fig. 7
                           2.   Loosen the bolts, then remove the bearing cap from
                                the differential carrier.
          SM10-426A
Fig. 8
                           3.   Remove the differential case assembly from the car-
                                rier.
          SM10-567A
Fig. 9
                           4. Remove the taper roller bearings at both ends of the
                              differential case and the side spacer located on the
                              right side of the differential case for gear ratio 3.636
                              only, by using a puller.
                           NOTE: ● Do not change the combination of the
                                       assembled taper roller bearing and its
                                       race.
                                   ● Always replace the bearings with their
           SM10-568                    original races.
Fig. 10
                           5.   Loosen the nuts and remove the ring gear from the
                                differential case.
           SM10-569
Fig. 11
                                               1 page 1
10-20 REAR AXLE                              Models FA and FB
SM10-570 SM10-453
Fig. 12
                                                7.   Component parts of the differential case assembly.
          SM10-572A               SM10-433
Fig. 14
                                                9. Remove the lock nut using a special tool.
                                                   Spread the staking of the nut completely with a chisel,
                                                   then loosen the nut.
                                                NOTE: Insufficient spread of the staked parts will
                                                        cause damage to the threads of the drive pin-
                                                        ion when loosening the nut.
                                                Special Tool: Socket wrench (09839 - 4104)
          SM10-434A              SM10-435A
Fig. 15
                                                10. Separate the bearing cage and the pinion gear with
                                                    a press.
                                  SM10-573
Fig. 16
                                     1 page 1
                                 Models FA and FB                               REAR AXLE 10-21
                                     11. Remove the taper roller bearing from the pinion gear
                                         using a puller.
                     SM10-574
Fig. 17
                                     12. Remove the retainer ring and then pull out the inner
                                         race for cylindrical roller bearing from the pinion gear
                                         using a puller.
                                                           WARNING
                                      The retainer ring is spring steel and may pop out.
                                      Wear safety glasses to protect your eyes.
          SM10-438   SM10-439
Fig. 18
                                     13. Remove the oil seal and the taper roller bearing outer
                                         races from the cage.
                     SM10-440
Fig. 19
                                     14. Component parts of the pinion assembly.
                     SM10-599
Fig. 20
                                INSPECTION
                                1.   INSPECTION OF THE DIFFERENTIAL CARRIER
                                     1. Check the flange coupling spline for wear and dam-
                                         age.
                                         Replace the coupling if damaged or worn.
                     SM10-575
Fig. 21
                                  1 page 1
10-22 REAR AXLE                 Models FA and FB
          SM10-576   SM10-444
Fig. 22
                                   3. Inspect the drive pinion and ring gear teeth surfaces
                                      for wear, stripping or damage, and replace both parts
                                      as a set when defects are found.
                                   NOTE: The drive pinion and ring gear must be re-
                                           placed as a set, not individually, because they
                                           are fitted to each other by lapping during
                                           manufacture.
                                           Replacement of only one part does not pro-
                     SM10-445              duce proper tooth contact, and gear strength
Fig. 23                                    drops excessively.
                                   4. Inspect the spider holes and surfaces of the differ-
                                      ential case that come in contact with the thrust wash-
                                      ers for wear or damage. Replace the case, if dam-
                                      aged or worn.
                     SM10-577
Fig. 24
                                   5.   Inspect the pinion for wear or damage and check the
                                        amount of wear of the bore with a cylinder gauge.
                     SM10-447
Fig. 25
                                   6.   Inspect the spider for damage, and check the amount
                                        of wear by measuring its journals with a micrometer
                                        to determine the spider to pinion clearance.
                                        When the clearance is beyond the service limit, re-
                                        place it.
                                           Standard Thickness:
                                               Side gear   1.9     - 2.1 mm (0.075 - 0.082 in.)
                                               Pinion gear 1.5     - 1.7 mm (0.060 - 0.066 in.)
                                           Service Limit:
                                               Side gear   1.7     mm (0.067 in.)
          SM10-449           SM10-450          Pinion gear 1.3     mm (0.051 in.)
Fig. 27
                                           8.   Measure the pinion backlash by using a dial gauge
                                                with a magnet base.
                                                When the backlash is beyond the service limit, re-
                                                place the pinion gear and/or side gear.
                            SM10-269B
Fig. 29
                                              1 page 1
10-24 REAR AXLE                           Models FA and FB
                                         ASSEMBLY
                                         1.   ASSEMBLY AND ADJUSTMENT OF DIFFERENTIAL
                                              CARRIER
                                              1. Assemble the differential case.
                                              NOTE: ● Align the aligning marks on cases.
                                                      ● Apply the adhesive (Lock agent) which is
                                                         equivalent to THREE BOND: 1360K on
                                                         threads.
                  SM10-452    SM10-453
                                                      ● Tighten the bolts to the specified torque.
Fig. 30
                                              Tightening Torque: 2,500 - 3,000 kg·cm (181- 217 lb·ft)
                              SM10-578
Fig. 31
                                              3.   Tighten the nuts to the specified torque.
                              SM10-455
Fig. 32
                                              4.   Install the side spacer to the right side of the differ-
                                                   ential case (For gear ratio 3.636 only).
                                                   Install the two tapper roller bearings, one to each end
                                                   of the differential case, using a press.
                             SM10-597A
Fig. 33
                                   1 page 1
                                 Models FA and FB                              REAR AXLE 10-25
                                                          WARNING
                                     The retainer ring is spring steel and may pop out.
                                     Wear safety glasses to protect your eyes.
          SM10-457    SM10-458
Fig. 34
                                    6.   Using a press, install the inner taper roller bearing
                                         to the drive pinion.
                      SM10-579
Fig. 35
                                    7.   Using a press, install the taper roller bearing outer
                                         races in the bearing cage.
          SM10-580    SM10-581
Fig. 36
                                    8.   Put the spacer to drive pinion.
                     SM10-582A
Fig. 37
                                    9.   Using a press, assemble the bearing cage and ta-
                                         per roller bearing on the drive pinion.
                      SM10-463
Fig. 38
                                                    1 page 1
10-26 REAR AXLE                                  Models FA and FB
                                                      10. Install the flange on the pinion shaft without oil seal,
                                                          and then tighten the flange lock nut to the specified
                                                          torque using a special tool.
                                   SM10-464A
Fig. 39
                                                      11. Measure the preload of the drive pinion bearings.
                                                          If the preload is out of the specified limits, adjust it
                                                          as follows.
                                                          Use a thinner spacer to increase and a thicker one
                                                          to decrease preload. When new bearings, use the
                                                          spacer of 14.175 mm (0.558 in.) at first and meas-
                                                          ure the preload. This will be helpful to select the
                                                          spacer for specified preload.
                                   SM10-465A              Tighten the flange lock nut to the specified torque
Fig. 40                                                   before re-checking.
                                                      a. Using a torque wrench.
                                    SM10-116
Fig. 41
                                                      12. When the preload is correct, remove the flange and
                                                          then install the new oil seal, flange and flange lock
                                                          nut.
                                                          Tighten the flange lock nut to the specified torque.
                                          13. Lock the flange lock nut by staking the lip into the
                                              pinion shaft slots.
                          SM10-583B
Fig. 44
                                          15. Measure the drive pinion fitting height (conical dis-
                                              tance) by using the pinion depth gauge.
                                              If the pinion fitting height is out of the specified value,
                                              adjust it with shim.
                                              Use a thinner shim to decrease and a thicker shim
                                              to increase the pinion fitting height.
              F
                           SM10-059
Fig. 47
                                           1 page 1
10-28 REAR AXLE                          Models FA and FB
                             SM10-584A
Fig. 49
                                            17. Install and tighten the bearing lock washers with bolt
                                                and nut, and then stake the lock nut as shown.
                  SM10-472    SM10-493
Fig. 50
                                            18. Mount the differential case assembly on the differ-
                                                ential carrier.
                             SM10-567A
Fig. 51
                                            19. Install the adjusting nut and bearing cap on the dif-
                                                ferential carrier and tighten the cap temporarily with
                                                bolts.
                                            NOTE: Align the match marks of the cap and the dif-
                                                  ferential carrier.
                              SM10-585
Fig. 52
                                    1 page 1
                                  Models FA and FB                            REAR AXLE 10-29
          SM10-586    SM10-587
Fig. 53
                                     21. Strike the bearing cap with a copper hammer.
                      SM10-588
Fig. 54
                                     22. Measure the gear backlash at four points using a dial
                                         gauge with a magnet stand. If the measured value
                                         is out of specified value, adjust the gear backlash by
                                         turning the adjusting nuts, loosening one side one
                                         notch and tightening the other side one notch.
                     SM10-478A
Fig. 57
                                    1 page 1
10-30 REAR AXLE                   Models FA and FB
                      SM10-072B
Fig. 58
                                     b)   Heel and face contact.
          A       B
                                                   A: Replace (Heel contact)
                  SM10-072C
Fig. 59
                                     24. Measure the total preload of the differential carrier
                                         bearings.
                                     NOTE: Total preload = Pinion bearing preload (Meas-
                                              ured in step 13. on page 10 - 27) + Side bear-
                                              ing preload (Refer to tables below).
                                         If the preload is out of the specified limits, adjust it
                                         with the adjusting nuts of the side bearings.
                                         Tighten both side adjusting nuts evenly to increase
                      SM10-590A          and loosen them to decrease preload and re-inspect
Fig. 60                                  the gear tooth contact.
                                     Special Tool: Adjuster tool (09665 - 1150)
                                     1. Using a torque wrench.
                                             SM10-592
Fig. 62
                                                             26. Install the lock plate.
                                             SM10-593
Fig. 63
                  SM10-595A
Fig. 66
                              3.   INSTALL THE AXLE SHAFT.
                   SM10-596
Fig. 67
                              4.   FILL THE DIFFERENTIAL WITH GEAR OIL.
                   SM10-486
Fig. 68