Repair a Cracked Caterpillar 789 Dump Truck Suspension Part | Machining & Welding

In this video we are machining and welding to repair a cracked Caterpillar 789 Dump Truck suspension part. This part is the top cap of the suspension Front Strut on the dump truck. There is a crack right through the weld joint holding the pin into the top cap and the pin has been damaged. To repair we need to machine out the damaged weld and pin before drilling, boring and weld prep machining the top cap to suit the new pin. We machine up a new pin using 150mm (6” inch) 4140 solid bar and then interference fit into the top cap before MIG welding with Hobart Fabco XL525 dual shield wire. The suspension part is then back in the lathe to finish machining the weld and pin down to size. We then drill and tap a 1“ (inch) hole in the pin to complete. Join our channel: We upload new videos every Friday at 5pm AEST! If you want to see more of our videos click LIKE & SUBSCRIBE! You can subscribe to our channel here: To see more follow us on online here: Instagram