436B Backhoe Loader Rear Differential Questions

Hello All,


The brakes recently went out on my 436B. Ended up removing the rear axle drive and disassembling it. Come to find out, whoever owned the machine before me had the friction discs and the steel brake plates in the wrong order resulting in heavy wear to the brake housing. Upon further inspection I noticed both 16 tooth gears (9R2424) had excessive wear on both ends rubbing up against the lock (9R2426) on the shaft assembly and on the centers where each gear meets in the middle. Both locks have deep radial grooves (over 1/8" thick) where the ends of the gears meet the locks as well as discoloration from heat. What I am trying to figure out is what caused this wear? I am having trouble comprehending what or why there was so much interference between the locks and gears. Will simply replacing the parts and putting the brake discs in the right order solve the problem? 9R7640 Axle GP-Drive and 9R8004 Axle AS-Rear.


Had I not lost the brakes due to the wear and brake piston over traveling and leaking I would not have known anything was wrong. Machine has been strong and reliable for the last 6 years that I owned it. I am the second owner of this machine. It was previously owned by a municipality with all service done by a local CAT dealer...


I do have the service and parts manual for this machine.