01-08-2009
I did the Montero LSD swap and here’s how I did it.
Tools needed:
12mm, 14mm sockets and wrenches
17mm, 22mm socket
10mm flare wrench
Rubber mallet
Screw drivers
Vice grips
Dial indicator with magnetic stand
Needle nose pliers
Removing the Open or LSD differential
Drain the differential fluid using a 22mm socket.

Bleed brakes and disconnect brake lines with a 10mm flare wrench from axle. Pass. Side has 1 line and the drv. Side has 2 lines disconnected. Then remove four 14mm nuts from the flange behind the drum on each side. Now you need to disconnect the drive shaft with a 12mm and 14mm wrench.

Next remove the 12mm bolt holding the emergency brake cables. Pull the axle’s loose, use a rubber mallet if needed. You just need to pull them out a few inches so the diff. will clear. Then remove ten 12mm bolts holding the differential. You should then be able to remove the diff. from the housing. I used some screwdrivers and mallet to pry the diff. loose. Try not to drop the housing on the ground, it’s a bit heavy.
Swapping the Open to LSD differential
Here’s the LSD.

I cut a hole in a 5 gal. bucket to hold the diff. carrier housing. This makes it much easier to pull the diff. in and out of the housing, but it could also be done on a workbench.

You can now remove the 17mm bolts from the bearing caps and remove or loosen the 12mm bolts from the locking plates. Then pull the LSD or Open diff. out.

Here’s a pic. of the Open and LSD diff.

If the LSD has a different ring gear, you need to swap out the ring gear from the Open to LSD. Remove the 14mm bolts, swap gears, and reinstall bolts using thread locker.

The stock 2gen rwd diff. is equipped with 3.909 ring gear/pinion the Montero/Raider usually had ring gears/pinions ranging from 4.22 to 4.625. Now reinstall the LSD into carrier housings and install the bearing caps and side bearing nuts. Now check the backlash. I did it on the workbench. I used Vise grips on the flange to prevent the pinion from moving.

Check backlash rocking the ring gear back and forth. Take a few readings around the circumference of the ring gear. Backlash should be between .0043 - .0063. Adjust backlash by turning the side bearing nut. I used a needle nose plier to turn the adjuster.

Once backlash is within spec. reinstall the locking plates. Also, check gear tooth pattern using some paint you can get at the local parts store.

Now the carrier housing w/LSD can be installed. Clean diff. housing and carrier housing mating surfaces and use silicone gasket sealer. Everything else can be reinstalled that was removed previously. Add brake fluid and bleed brakes and also fill diff. with GL-5 fluid with appropriate LSD additive to fill hole level. It should take 1.5 - 2 quarts to fill diff.