I have an infrared unit, and it's pretty darn useful. A little experimenting with it goes a long way. It would certainly indicate whether oil is being routed to coolers, etc.

Randy:
Did you ever resolve this problem? I have the exact same issue, and an convinced that my gauge is bad.
Thanks!
Pat

Hey Pat,
I did resolve my problem. It was the ground connection to the gage. I had checked the connections and thought they were good, but after alot of other troubleshooting I found it was the connection at the gage. I removed the gage and cleaned all of the connections with sandpaper and it seems to be working fine. This thing caused me alot of headaches.
Randy