1991 MAZDA MIATA 4WD

1990-91 DRIVE AXLES
Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
AXLE RATIO & IDENTIFICATION
See AXLE RATIO SPECIFICATIONS . To determine axle ratio, divide number of ring gear teeth by number
of pinion teeth.
AXLE RATIO SPECIFICATIONS
DESCRIPTION
An optional Limited Slip Differential (LSD) is available on Miata and RX7 models. Rear drive axles are
retained in the housing by tapered bearings and bearing retainers at axle housing outer ends on B2200 and
B2600i. Rear drive axle bearings on MPV 4WD are held in place by a pressed-on collar.
On front axle on B2600i (4WD) and MPV 4WD, and rear axle on Miata, Protege 4WD, RX7 and 929, drive
axles use CV joints to connect differentials to drive hubs.
LUBRICATION
CAPACITY
Application
No. of Teeth
Pinion/Ring Gear
Ratio
B220011/433.91:1
B2600i
Front & Rear11/413.73:1
MiataN/A4.30:1
MPV (Front & Rear)
A/T10/414.01:1
M/T11/433.91:1
Protege & 929N/AN/A
RX7
A/T (1) 11/433.9:1 or 4.1:1
M/T Non-TurboN/A4.1:1 or 4.3:1
M/T TurboN/A4.1:1
(1)Non-Turbo convertible only.
NOTE: For models with independent suspension, see REAR AXLE SHAFTS (vehicles
that are normally only FWD), or AXLE SHAFTS
- FRONT article in this section
for axle shaft overhaul.

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 1 © 2005 Mitchell Repair Information Company, LLC.
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Sunday, July 05, 2009 2:17:05 PMPage 1 © 2005 Mitchell Repair Information Company, LLC.

DIFFERENTIAL CAPACITY SPECIFICATIONS (1)
FLUID TYPE
DIFFERENTIAL LUBRICATION SPECIFICATIONS
(1)
TROUBLE SHOOTING
See TROUBLE SHOOTING - BASIC PROCEDURES article in the TROUBLE SHOOTING Section.
REMOVAL & INSTALLATION
REAR AXLE SHAFTS & BEARINGS
Removal (B2200 & B2600i)
1. Raise and support vehicle. Remove rear wheels. Remove brake drum and shoes. Using a dial indicator,
measure axle flange lateral movement. If bearing play is not within specification, bearing shim must be
adjusted during installation. See END PLAY SPECIFICATIONS
.
2. Disconnect brake line from wheel cylinder. Plug line openings. Disconnect parking brake cable. Remove
backing plate retaining nuts. Remove axle shaft and backing plate as an assembly.
ApplicationQts. (L)
B2200 (Front & Rear)1.3 (1.2)
B2600i
Front1.6 (1.5)
Rear1.8 (1.7)
Miata.69 (.65)
MPV 2WD1.6 (1.5)
MPV 4WD
Front1.8 (1.7)
Rear1.6 (1.5)
Protege 4WD.69 (.65)
RX7
Non-Turbo1.4 (1.3)
Turbo1.5 (1.4)
9291.4 (1.3)
(1)Fill to lower edge of filler plug hole.
ApplicationSpecification
Above 0°F (-18°C)GL-5/SAE 90W
Below 0°F (-18°C)GL-5/SAE 80W
(1)Fill to lower edge of filler plug hole.

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 2 © 2005 Mitchell Repair Information Company, LLC.

3. Using Bearing Nut Wrench (49 0603 635A ) and Shaft Holder (49 S120 645A ), remove bearing lock nut
from axle shaft. Remove bearing and bearing retainer from axle using Puller (49 S120 520A ). Remove
outer race from hub.
END PLAY SPECIFICATIONS
(1)
Installation
1. Press new oil seal and bearing outer race into bearing retainer. Coat bearing race and outer seal with
grease. Tap inner oil seal flush with end of axle housing. Coat inner seal lip with grease.
2. Position brake backing plate onto axle shaft. Install spacer against backing plate with chamfer facing
backing plate. Using Press Attachment (49 S120 748 ) and a press, install wheel bearing onto axle shaft.
Standard press force is 4.6-6.7 tons (4200-6100 kg). If press fit force is too high or too low, replace the
bearing collar or shaft.
3. Using Bearing Nut Wrench (49 0603 635A ), install bearing lock nut to axle shaft and tighten to 145-217
ft. lbs. (196-245 N.m). Bend tab up into groove. Install one axle shaft into axle housing. Tighten backing
plate nuts to specification. Install dial indicator on backing plate and check drive axle end play.
4. To adjust end play, remove axle and insert appropriate size adjustment shim between axle hub and
housing. End play for second drive axle installed should be set to normal end play clearance of .002-
.010" (.05-.25 mm), with both axles installed.
5. Install parking brake cable, attaching pin and brake line. Install brake shoes and actuating hardware.
Bleed brake system. Install wheel and tire.
BEARING RETAINER SHIMS (B2200 & B2600i)
MPV 4WD
NOTE: On B2200 and B2600i, left axle bearing lock nut has left-hand threads.
ApplicationIn. (mm)
B2200 & B2600i
One Axle Installed.026-.037 (.65-.95)
Both Axles Installed.002-.010 (.05-.25)
(1)Check at axle flange with dial indicator.
NOTE: Ensure end play for first drive axle is within specification before inserting
second drive axle. Use shims to adjust end play if necessary.
Part NumberThickness In. (mm)
083 26 165.004 (.10)
083 26 166.006 (.15)
083 26 167.020 (.50)
083 26 168.030 (.75)

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 3 © 2005 Mitchell Repair Information Company, LLC.

Removal (Front - B2600i & MPV 4WD)
1. Raise and support vehicle. Remove engine skid plate. Drain differential. On MPV 4WD, remove tie rod
end and lower arm. Remove front axle shafts. See AXLE SHAFTS
- FRONT article. Mark drive shaft
position, and remove drive shaft.
2. On B2600i, remove differential subframe mounting bolts and nuts. Remove differential, Remote Free
Wheel (RFW) and subframe assembly from vehicle. Remove RFW assembly from right side of
differential housing. Pull drive coupler from carrier. Remove differential carrier retaining bolts. Remove
differential carrier.
3. On MPV 4WD, remove differential housing mounting bolts and mount at end of Remote Free Wheel
(RFW) extension housing. Remove differential and extension housing from vehicle. Remove RFW
assembly from right side of differential housing. Pull drive coupler from carrier. Remove differential
carrier retaining bolts. Remove differential carrier.
Installation
To install, reverse removal procedure. See Fig. 2 or Fig. 3 . Apply Sealant (8527 77 739 ) to carrier mating
flange. Align marks made during removal. Refill differential with lubricant. Tighten all fasteners to
specification. See TORQUE SPECIFICATIONS
.

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 5 © 2005 Mitchell Repair Information Company, LLC.

Fig. 3: Installing Front Differential (MPV 4WD)
Courtesy of MAZDA MOTORS CORP.
Removal; Rear - B2200, B2600i, MPV 2WD, PROTEGE 4WD, RX7, 929
1. Raise and support vehicle. Drain differential. Mark drive axles and drive shaft positions. On B2200,

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 7 © 2005 Mitchell Repair Information Company, LLC.

B2600i and MPV, remove brake drum and drive axles. See REAR AXLE SHAFTS & BEARINGS. On
Protege 4WD, RX7 and 929, disconnect CV joint drive axles from differential assembly and wire aside.
2. On all models, mark flanges and disconnect drive shaft. Remove ABS sensor (if equipped). On RX7,
remove rear exhaust system and differential mount on left side of pinion flange. Remove hanger mounts
and allow left side to hang down. Disconnect sublinks and remove differential.
3. On Protege 4WD and 929 models, remove differential housing assembly-to-chassis mounting bolts.
Remove differential housing assembly from vehicle. On all models, remove differential carrier-to-
housing nuts. Remove differential carrier.
Installation
To install, reverse removal procedure. Apply Sealant (8527 77 739 ) to carrier mating flange. Align marks made
during removal. Refill differential with correct type and amount of lubricant. Tighten all fasteners to
specification. See TORQUE SPECIFICATIONS
.
Fig. 4: Exploded View of Differential Assembly (RX7)

Courtesy of MAZDA MOTORS CORP.
Removal (Miata)
1. Raise and support vehicle. Drain differential. Mark flanges and remove drive shaft. Note locations and
disconnect wiring harness from Power Plant Frame (PPF). See Fig. 5
.

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 8 © 2005 Mitchell Repair Information Company, LLC.

4. Subtract thickness from 3.701" (94.00 mm). Difference should be .004-.016" (.10-.40 mm). If clearance is
not as specified, install oversize thrust washers. See RX7 DIFFERENTIAL SPECIFICATIONS
.
5. Install parts in proper order. See Fig. 8
. Before installing thrust washers, coat with grease. When
installing conical springs, ensure concave side faces side gears. Align differential case and cover
alignment marks. Apply locking compound to rear face of ring gear. Install ring gear and tighten ring gear
retaining bolts to 51-61 ft. lbs. (69-83 N.m).
RX7 DIFFERENTIAL SPECIFICATIONS (LIMITED SLIP)
Pinion Assembly (B2200, B2600i, Miata, Protege 4WD & 929)
1. Using a press, install pinion bearing races in differential housing. Place original spacer, rear bearing and
Bearing Collar (49 H027 001 ) onto Drive Pinion (49 8531 565 ). Secure collar with "O" ring. Install
assembly into differential housing.
2. Install front bearing, Collar (49 8531 567 on 929 or 49 U027 001 on B2200 and B2600i), companion
flange, washer and original drive pinion nut. See Fig. 11
. Tighten flange nut so assembly can be turned
by hand.
3. Place a dial indicator on Pinion Height Gauge (49 0727 570 ). Place pinion height gauge on a flat surface
and zero dial indicator. Position Gauge Block on top of Drive Pinion (49 F027 001 ). See GAUGE
BLOCK SELECTION .
GAUGE BLOCK SELECTION
ApplicationIn. (mm)
Friction Disc Thickness
Standard.079 (2.0)
Limit.075 (1.9)
Friction Plate
Standard.079 (2.0)
Limit.075 (1.9)
Oversize.083 (2.1)
Thrust Washer
Standard.063 (1.6)
Limit.055 (1.4)
Oversize.071 (1.8)
ApplicationUse Gauge Block No.
Front Differential
B2600i
& MPV
4WD49 0305 555
Rear Differential
B220049 0305 555
B2600i,
Protege 49 0660 555

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 16 © 2005 Mitchell Repair Information Company, LLC.

4. Set pinion height gauge on top of gauge block. Set dial indicator to measure distance to a point where
side bearing sits. Measure lowest point. See Fig. 11
. Measure both sides. Add both measurements
together and divide sum by 2.
5. If measurement is not zero, replace pinion spacer. Spacers are available in a range of .1213-
.1366" (3.081-3.470 mm), in .001" (.03 mm) increments. Remove dummy pinion shaft. Press rear pinion
bearing on pinion shaft.
6. Install pinion shaft, spacer, front bearing, collapsible spacer and companion flange in differential housing.
DO NOT install pinion seal at this time. DO NOT exceed one ton force or collapsible spacer will be
damaged.
7. Temporarily tighten drive pinion nut. Turn companion flange by hand to seat bearing. Tighten drive
pinion nut to 94-130 ft. lbs. (128-177 N.m). Check pinion bearing preload, at drive pinion nut. See
PINION PRELOAD SPECIFICATIONS
. If pinion bearing preload is not as specified, replace
collapsible spacer and recheck preload.
8. Remove drive pinion nut and companion flange. Install pinion seal. Apply oil to seal lip. Install
companion flange. Using a new drive pinion nut, tighten nut to 94-130 ft. lbs. (128-177 N.m). Recheck
pinion bearing preload.
PINION PRELOAD SPECIFICATIONS
4WD &
929
Miata49 N027 001
ApplicationINCH lbs. (N.m)
B2200 & 92911.3-15.6 (1.3-1.8)
B2600i 4WD
Front11.3-15.6 (1.3-1.8)
Rear7.8-12.2 (0.9-1.4)
Miata & Protege 4WD (Rear)2.6-6.1 (0.3-0.7)
MPV 4WD
Front7.8-12.2 (0.9-1.4)
Rear11.3-15.6 (1.3-1.8)
RX7
Non-Turbo7.8-12.1 (0.9-1.4)
Turbo11.3-15.6 (1.3-1.8)

1991 Mazda MX-5 Miata
1990-91 DRIVE AXLES Differentials & Drive Axles - 929, B2200, B2600i, MX-5 Miata, MPV, Protege & RX-7
Microsoft
Sunday, July 05, 2009 2:17:01 PMPage 17 © 2005 Mitchell Repair Information Company, LLC.