When your checking fan per IowaDan be sure to clean heater and evaporator core. All the fan in the world won't shuve air threw plugged cores. We have not added a relay to zoop up fan speed but have replace many fan switches and the wires ends that plug into it. I think it is a great idea to add a relay to at least high speed but you may need a electical guy to do this. We use the relay kit listed in the l2 parts manuals for many locations where we want to add a relay. It is listed in the air cond condeser fan area and it was a kit to replace old style relay with new style plug in. It comes equiped with harness that can be adapted. They do use relay on new combines and I believe for high speed only. If you have the older R72 before they went with larger hoses out of air cond unit you best look back a few posts to find where some guys have enlarged some holes to allow more air up side posts and blocked off a couple vents that do little good for air draft. Good luck
