Hi - if you are driving an old Subaru with 4 WD; and need to replace the Rear Wheel Bearings - you will find that a Special Lock Nut Ring exists on the ‘inside’ of each hub - which MUST be removed to drive out and replace the bearings. This Ring Nut is installed with a torque of 127(min) to 163(max) foot pounds… Subaru calls out a ‘special’ tool to help remove the Ring Nut - p/n (WRENCH 925550000) The Repair manual doesn’t mention it - but this Ring Nut Wrench also has p/n of: SU-022
This tool is discontinued and is VERY hard to come by… HOWEVER - Performance Tool makes a similar tool which WILL work - after a simple modification… the W1271 (by PT) and available from various outlets such as O’Reilly’s or AutoZone and others for around $20 - works quite well - IF you CUT OFF two of the protruding ‘nubs’. 180 degrees apart. This leaves two nubs still on the tool - and it will NOW FIT the Subaru drive axle… and you can unscrew the Ring nut. The tool is not rated for ‘impact’ - but I found that worked quite well; and quickly got it unscrewed. I also weld - so I welded the two ‘nubs’ which I cut off - back onto the tool - to help it fit. Although that wasn’t really necessary. And If you just cut off two opposing nubs and don’t weld them back on - it actually would still probably work for the applications for which it is designed and sold… Just a head up… the PT W1271 can be substituted for a Subaru 925550000 or SU-022 if you cut off two opposing nubs… When replacing older Subaru rear wheel bearings.