I'm documenting the installation of a Lokka "aussie" locker in the 12-bolt on my '90 Trooper.
I started by draining the diff, jacking up the rear, putting stands under the rear axle, and putting the tires under the rear for extra security.
I got under the truck a little prematurely and disconnected the drive shaft, would have been easier to do this after pulling the axles out (would have kept me from getting in and out from under the truck)
Remove the rear calipers 2 bolts each and hang either on the rear springs or the tires now sitting under the rear.
Remove the axle flange, 4 nuts *these attach to free floating studs with a bracket between 2, it may be necessary to make sure the stud remains pulled out as you remove the nut. In the off chance that one stud free spins even when pulled out, you will need to remove the disc and wedge a screwdriver or pry bar between the stud head and the bracket meant to keep it from turning. I know because it happened to me, wouldn't expect it any other way.
Now get back under there and remove all the bolts and 2 nuts holding the 3rd asm in place. It probably won't budge afterwards, a good size punch/prybar and a hammer tapping from the top should get it loose. Then pull it out, keep in mind if you don't eat lots of wheaties you won't be removing this with one hand......it's heavy. It's out in the pic sorry both hands were occupied getting it out LOL.
Put the 3rd in a vice (not like pictured) clamp it along the mounting edge so the input shaft is parallel to the bench.....trust me it's easier to lock in this way.
Mark the caps and the ring gear to carrier. I used the letters a,b,c,d on the caps (one on each side of the cap) and e on the ring gear/carrier. I'm a little obsessive and even marked the cap bolts
Remove the caps w/bolts, then pull the entire carrier asm out. I set the races aside keeping them with their perspective caps (i.e. Left and Right) Make sure you marked the ring gear to carrier, then remove the bolts and then the ring gear.
*edit note* the instructions tell you not to mess with the end cap adjustment when removing the caps, pay no attention there are none, the instructions are somewhat generic.
Remove the Cross Shaft pin use a punch, it only comes out from one side
To avoid confusion, this is where you insert the punch to get it out. Look at the small hole.
Slide the cross shaft out and inspect it, mainly where the gears ride on it. The instructions say even .002's of wear could be an issue with the locker.
Rotate the gears and remove, NOTE when you remove the spline gears make sure you note which side of the carrier they came from as well as any thrust washer.
Apply a light coat of grease to the new spline gears, and install the thrust washers removed from the original gears.
Install the new spline gears into the carrier and rotate a few times to help seat them in place.
grease the cam gears, put a little more than I did it will help hold them in place.......I obviously didn't put enough on
grease the pins and install in the slotted groves with the tit down, grease the spacer while your at it
put the asm into the diff
use a screwdriver or a pic (dental tools work great) to move the pins into the holes on the opposite sides
install the springs and make sure they fully seat over the tit on the pin, the dental tool helped alot
re-install the cross shaft
reinstall the cross shaft pin (from this direction)
take a punch and detent the housing so the pin won't back out
re-install the ring gear *make sure you align it with the carrier in the previously marked position*
reinstall the ring gear bolts with loc-tite
torque to specs
in this pattern
when torquing it helps to put the carrier in a vice like this
reinstall the carrier and caps *previously marked*
torque to specs
double check everything and get one good last look at it before it goes in the axle
add some sealant as shown and torque properly
reinstall your drive shaft, fill axle with 80w90 1.8L ,reinstall the tires, perform the lock out test per instructions , remove the jacks and lower, test drive
I started by draining the diff, jacking up the rear, putting stands under the rear axle, and putting the tires under the rear for extra security.
I got under the truck a little prematurely and disconnected the drive shaft, would have been easier to do this after pulling the axles out (would have kept me from getting in and out from under the truck)
Remove the rear calipers 2 bolts each and hang either on the rear springs or the tires now sitting under the rear.
Remove the axle flange, 4 nuts *these attach to free floating studs with a bracket between 2, it may be necessary to make sure the stud remains pulled out as you remove the nut. In the off chance that one stud free spins even when pulled out, you will need to remove the disc and wedge a screwdriver or pry bar between the stud head and the bracket meant to keep it from turning. I know because it happened to me, wouldn't expect it any other way.
Now get back under there and remove all the bolts and 2 nuts holding the 3rd asm in place. It probably won't budge afterwards, a good size punch/prybar and a hammer tapping from the top should get it loose. Then pull it out, keep in mind if you don't eat lots of wheaties you won't be removing this with one hand......it's heavy. It's out in the pic sorry both hands were occupied getting it out LOL.
Put the 3rd in a vice (not like pictured) clamp it along the mounting edge so the input shaft is parallel to the bench.....trust me it's easier to lock in this way.
Mark the caps and the ring gear to carrier. I used the letters a,b,c,d on the caps (one on each side of the cap) and e on the ring gear/carrier. I'm a little obsessive and even marked the cap bolts
Remove the caps w/bolts, then pull the entire carrier asm out. I set the races aside keeping them with their perspective caps (i.e. Left and Right) Make sure you marked the ring gear to carrier, then remove the bolts and then the ring gear.
*edit note* the instructions tell you not to mess with the end cap adjustment when removing the caps, pay no attention there are none, the instructions are somewhat generic.
Remove the Cross Shaft pin use a punch, it only comes out from one side
To avoid confusion, this is where you insert the punch to get it out. Look at the small hole.
Slide the cross shaft out and inspect it, mainly where the gears ride on it. The instructions say even .002's of wear could be an issue with the locker.
Rotate the gears and remove, NOTE when you remove the spline gears make sure you note which side of the carrier they came from as well as any thrust washer.
Apply a light coat of grease to the new spline gears, and install the thrust washers removed from the original gears.
Install the new spline gears into the carrier and rotate a few times to help seat them in place.
grease the cam gears, put a little more than I did it will help hold them in place.......I obviously didn't put enough on
grease the pins and install in the slotted groves with the tit down, grease the spacer while your at it
put the asm into the diff
use a screwdriver or a pic (dental tools work great) to move the pins into the holes on the opposite sides
install the springs and make sure they fully seat over the tit on the pin, the dental tool helped alot
re-install the cross shaft
reinstall the cross shaft pin (from this direction)
take a punch and detent the housing so the pin won't back out
re-install the ring gear *make sure you align it with the carrier in the previously marked position*
reinstall the ring gear bolts with loc-tite
torque to specs
in this pattern
when torquing it helps to put the carrier in a vice like this
reinstall the carrier and caps *previously marked*
torque to specs
double check everything and get one good last look at it before it goes in the axle
add some sealant as shown and torque properly
reinstall your drive shaft, fill axle with 80w90 1.8L ,reinstall the tires, perform the lock out test per instructions , remove the jacks and lower, test drive