LOCKING HUBS
1991 Mitsubishi Montero
1991 DRIVE AXLES
Locking Hubs
Mitsubishi: Montero, Pickup
DESCRIPTION
Automatic hubs are engaged by rotational force of axle shaft
when 4WD is selected at transfer case. Automatic hubs disengage when
2WD is selected or vehicle is driven in Reverse. Cams, brakes and
springs are used to lock or unlock automatic hubs.
Engagement is accomplished through gears and spring actions
within hub. When hub is locked, hub brake engages inner hub, which is
connected to axle shaft by inner splines of hub. Hub brake is
connected to hub body by outer splines.
REMOVAL
1) Hub must be unlocked. To unlock hub, place transfer case
lever in 2H position and move vehicle in Reverse approximately 4-6
feet.
2) Remove cover from locking hub. If hub cover cannot be
loosened by hand, wrap shop towel around cover and use an oil filter
wrench to loosen cover.
3) Raise and support vehicle. Remove wheel assembly. Using
snap ring pliers, remove snap ring and shim from end of axle. Remove
locking hub retaining bolts. Remove locking hub.
INSTALLATION
1) To install, reverse removal procedure. Apply sealant to
contact areas between locking hub assembly and hub/rotor assembly.
Ensure sealant is NOT applied on outer areas of hub/rotor assembly
toward brake contact areas.
2) Align locking hub assembly key area with steering knuckle
key way area. Loosely install locking hub assembly on hub/rotor
assembly. Ensure locking hub assembly fully contacts hub/rotor
assembly.
3) Install locking hub retaining bolts. Tighten bolts to 36-
43 ft. lbs. (49-58 N.m). Using spring scale attached to wheel stud,
measure turning resistance required to rotate hub/rotor assembly.
4) Turning resistance should NOT exceed 3.1 lbs. (1.4 kg). If
turning resistance exceeds specification, check for incorrect
installation of locking hub assembly or components.
5) Install shim and snap ring on drive axle. Rotate drive
axle until maximum end play is obtained. Using a dial indicator, check
drive axle end play.
6) Drive axle end play should be .008-.020" (.20-.51 mm). If
axle end play is NOT within specification, adjust end play by changing
axle shaft shim. Install hub cover. Tighten hub cover 13-25 ft. lbs.
(18-34 N.m).
OVERHAUL
DISASSEMBLY
1) Remove locking hub. See REMOVAL & INSTALLATION. Push brake
"B" in hub housing and remove housing "C" ring. See Fig. 1. Using
Adapter (MB990811-01), lightly press drive gear assembly and remove
"C" ring from retainer "B". Slowly release drive gear assembly.
2) Remove drive gear assembly, slide gear assembly and return
spring. Remove slide gear "C" ring. Remove shift spring.
Fig. 1: Exploded View of Locking Hub
Courtesy of Chrysler Motors.
INSPECTION
1) Check drive gear and slide gear splines for damage. Check
cam portion of retainer "A" for wear or damage. Check cam for wear and
damage. Check slide gear and housing tooth surfaces for damage. Check
retainer "B" and housing contact surfaces for wear and damage.
2) Check brake assembly thickness. See Fig. 2. Assemble brake
"A" and brake "B". Using slide calipers, measure thickness of
assembled brake at both brake "A" lugs.
3) Standard thickness is .413" (10.49 mm). Minimum thickness
is .378" (9.60 mm). If measured thickness is less than minimum
thickness, replace brake "A" and brake "B".
4) Check length of return spring. Measure length "A" of
spring. Ensure length "A" is 1.38" (35.1 mm). See Fig. 3. If length
"A" is NOT as specified, replace return spring.
5) Check length of shift spring. Measure length "B" of
spring. Ensure length "B" is 1.18" (30.0 mm). See Fig. 3. If length
"B" is NOT as specified, replace shift spring.
Reassembly Pack grooves of retainer "B" with multipurpose
grease and apply grease to attaching surfaces of all components. To
complete assembly, reverse disassembly procedure.
Fig. 2: Measuring Brake Assembly Thickness
Courtesy of Chrysler Motors.
Fig. 3: Measuring Lengths of Return Spring & Shift Spring
Courtesy of Chrysler Motors.
TORQUE SPECIFICATIONS
TORQUE SPECIFICATIONS
Application Ft. Lbs. (N.m)
Hub Cover ........................... 13-25 (18-34)
Locking Hub Bolts ................... 36-43 (49-58)
