This specially designed four pin tool, with cormoly billet bulkhead pins, is used on vehicles using pressed on pulleys. The four strengthened pins in
LML Fan Pulley on LLY Chevy and GMC Duramax Diesel Forum
Schley Products, Inc 61500B Gm Water Pump 4 Pin Fan Clutch Pulley Holding Tool : Automotive
GM Diesel 4 Pin Fan Clutch Water Pump Pulley Holder
GM Diesel 4 Pin Fan Clutch Water Pump Pulley Holder
Tool for fan clutch nut Chevy TrailBlazer, TrailBlazer SS and
NexADD Fan Clutch Wrench Set 32mm & 36mm Water Pump Holder
dodge fan clutch wrench from
Mercedes MBE4000 Engine Fan Clutches for Sale
GM Water Pump 4 Pin Fan Clutch Pulley Holding Tool — Ferrum Tools
How to Replace a Water Pump Pulley