SPRING AS-GAS 4744056 - Caterpillar

Because the strength of the frame may decrease, some manufacturers do not recommend welding onto a chassis frame or rail. Consult the OEM of the equipment or your Caterpillar dealer regarding welding on a chassis frame or rail.
To help avoid damage to the electronic controls, proper welding procedures are necessary. Before you weld on equipment with electronic controls, observe the following precautions:
Turn off the engine. Place the engine control switch in the OFF position.
If the engine has a battery disconnect switch, open the switch. Otherwise, disconnect the negative "-" battery cable from the battery of the equipment.
Do not ground the welder to electrical components such as the ECM or sensors. Improper grounding can cause damage to the drive train bearings, hydraulic components, electrical components, and other components.Clamp the ground cable from the welder to the component that will be welded. Place the clamp as close as possible to the weld. This will help reduce the possibility of damage.
Clamp the ground cable from the welder to the component that will be welded. Place the clamp as close as possible to the weld.
Protect wiring harnesses from welding debris and from spatter. Use proper welding procedures.