Mazda Trucks 1994-1998 Repair Guide

Center Bearing



Navajo and B Series Pick-up Models

See Figure 1

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Fig. Fig. 1: Cutaway view of the coupling shaft and center support bearing

  1. Remove the driveshaft from the vehicle.
  3. Separate the driveshaft from the coupling shaft maintaining proper orientation.
  5. Remove the nut retaining the half round yoke to the coupling shaft and remove the yoke.
  7. Check the center bearing support for wear by rotating the outer area while holding the coupling shaft. If any wear or roughness is evident, replace the bearing.
  9. Inspect the rubber insulator for evidence of hardness, cracking or deterioration. Replace if damaged in any way.
  11. Re-install the coupling shaft yoke.

Be sure the yoke is re-installed on the coupling shaft in the same orientation as it was originally installed. The orientation is critical so that proper driveshaft balance and U-joint phasing is maintained. Tighten the retaining nut to 100-120 ft. lbs. (135-162 Nm).

  1. Re-assemble the driveshaft to the coupling shaft, maintaining proper orientation.

MPV Models

See Figures 2, 3 and 4

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Fig. Fig. 2: Before separating the two halves of the rear driveshaft assembly, matchmark the positioning of the halves for correct reassembly

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Fig. Fig. 3: When separating the front half from the rear half, use two, 14 mm box wrenches and remove the four mounting nuts

The center support bearing is a sealed unit which requires no periodic maintenance. The following procedure should be used if it becomes necessary to replace the bearing. You will need a pair of snapring pliers for this job.

  1. Remove the driveshaft assembly.
  3. To maintain driveline balance, matchmark the rear driveshaft, the center yoke and the front driveshaft so that they may be installed in their original positions.
  5. Remove the center universal joint from the center yoke, leaving it attached to the rear driveshaft. See the following information for the correct procedure.
  7. Remove the nut and washer securing the center yoke to the front driveshaft.
  9. Slide the center yoke off the splines. The rear oil seal should slide off with it.
  11. If the oil has remained on top of the snapring, remove and discard the seal. Remove the snapring from its groove. Remove the bearing.
  13. Slide the center support and front oil seal from the front driveshaft. Discard the seal.
  15. Install the new bearing into the center support. Secure it with the snapring.
  17. Apply a coat of grease to the lips of the new oil seals, and install them into the center support on either side of the bearing.
  19. Coat the splines of the front driveshaft with grease. Install the center support assembly and the center yoke onto the front driveshaft, being sure to match up the marks made during disassembly.
  21. Install the washer and nut. Tighten the nut to 120-130 ft. lbs. (163-177 Nm).
  23. Check that the center support assembly rotates smoothly around the driveshaft.
  25. Align the mating marks on the center yoke and the rear driveshaft, and assemble the center universal joint.
  27. Install the driveshaft. Be sure that the rear yoke and the axle flange re aligned properly.