Replacement CJ7 Locking Hubs

New Mile Marker 480 Locking Hub

Got off of a beautiful trail the other day and went to unlock my hubs only to find that the driver side was stuck.  I finally had to take a vice-grip to it in order to force the dial over to 2 wheel drive.

Upon inspection, I was shocked to find many plastic parts/gears and the dial itself...!  I also found one of the ring gears to be cracked which caused the bind.

I began scouring many sites on locking hubs only to find out that the Warn and SuperWench no longer make their much recommended locking hubs for any of the CJ7 models.  I did find that MileMarker does make a quality, all metal, replacement and is well reviewed.

CJ Universal (6-bolt 27 spline)    ’72-’86    Mile Marker #457    1 Pair

CJ Universal (5-bolt 27 spline)    ’80-’86    Mile Marker #470    1 Pair

AMC ran various combinations of axles so be sure to check bolt pattern.  Mine is a mid-year 1986 with the Dana 30 front axle and 5 bolt pattern.

Parts:

Mile Marker #470

10 each 3/8-16 x 1 1/2" Grade 5 zinc plated, hex head bolts

Gasket Maker (I used Permatex 25228 The Right Stuff)

Removal Procedure:

1. Put the front end on jack stands so that tires clear ground.
2. Remove cap from existing locking hubs.
3. Remove circlip from axle spindle.
4. Remove locking hub bolts and pull straight off.  I had to tap with a dead blow hammer.

Installation Procedure:

• Clean off spindle (could be a good time to inspect wheel bearings).
• Dress surface of wheel hub and address if necessary.
• Before removing locking hub cap, mark orientation of cap to hub with a piece of painters tape and don't rotate the dial after removing cap.
• Separate the locking hub cap from the locking hub.
• Wipe, with denatured alcohol, mating surfaces of wheel hub and locking hub.

• Note: I decided not to use the paper gaskets that came with the locking hubs.
• Create a bead of the gasket maker on the wheel hub only; allow 15 minutes to skin over.
• Then finger tight the locking hub to the wheel hub until there is squeeze out.  Clean up squeeze out.
• Wait the prescribed time, at least an hour, before torquing down to 30 ft-lbs.
• Reinstall circlip to spindle.  You may need to use a pry bar at the u-joint behind the wheel to push the spindle deeper into the wheel hub to expose the groove for the circlip.  Make sure the circlip is in the groove.

• Clean mating surfaces of locking hub and cap.
• Apply gasket maker on locking hub mating surface only; allow 15 minutes to skin over.

• While aligning the painters tape on the hub and the cap, finger tight the locking hub to the wheel hub until there is squeeze out.  Clean up squeeze out.
• Wait the prescribed time, at least an hour, before torquing down to 30 in-lbs.
• Once the cap is secured to the hub it is okay to turn the selector dial.

The Mile Marker locking hubs come also with a nifty little wrench that gives a little more leverage if needed... thoughtful.

Hope this helps,

Mike