CaptHamster

Sounds like your fan clutch may have died, and it is no longer allowing the cooling fan to engage. You should hear a distinct "roar" fan noise when the fan clutch engages... When cruising down the highway there's enough air flowing through the...

Check out this thread as one of the members here offers a rebuild service for the driver's window relay. I had my relay rebuilt through him a couple years back and it works flawlessly now, same issues as you. This should solve your problem!

@Spook50 What did you end up doing for a radiator? I still have the Mishimoto and it has been trouble free. A couple hunting trips in southern Arizona in 117 degree heat with no issues, kept it cool and happy even with the A/C full blast.