AUSSIE LOCKER™ INSTALLATION SUPPLEMENT FOR JEEP REAR AXLES AMC 20   While the installation is generally described in the manual that is included with your new Aussie Locker, the stock AMC-20 rear axle uses a thrust block to maintain the correct pre-load on the axle shaft bearings. It is imperative that you re-use this part to continue to maintain the correct pre-load. When installing your new locker, use the following additional steps:   1. Remove the thrust block (a cylindrical part with an oblong hole in the middle) from the existing differential.   2. During the installation of your Aussie Locker, place the thrust block inside the splines of one of the axle gears.   3. Install the Aussie Locker per the instructions in the manual, being careful to keep the axle gear horizontal and not let the thrust block fall out.   4. Before the final step of installing the pinion shaft in the differential case, use an axle shaft or long rod and carefully push the thrust block out of the axle gear through the spacers and into the center of the assembly.   5. Reach in through the recess in the cam gears and rotate the thrust block so that the hole in the middle lines up with the cam gear recesses.   6. Rotate the whole assembly so that the pinion shaft will pass through all the parts. (The holes in the spacers will hold the thrust block centered.)   7. Install the pinion shaft and finish the installation per the instructions in the manual.   8. When installing the axle shafts, it is very important to be sure that the axle shaft flange shims are installed correctly. The procedure is contained in the Jeep shop manual. In general, if the shims and pre-load were correct before the installation, then nothing has changed and re-installing everything will suffice. If no shims are present or if the flanges seem to not seat on the hub with reasonable torque on the bolts, then the shim pack should be set up as described in the Jeep manual. Axle bearing pre-load is very important to the operation of the axle assembly.   Note: The above procedure applies to the stock rear axle assembly with two-piece axle shafts and tapered roller axle bearings. If the axles have been changed to after-market one-piece shafts then the thrust block may be omitted.   If you have any questions e-mail us at installation@offroadlockers.com AMC-20 Supplement 1 31121