Wtfo?

jrlegacy23 said
Sounds like you may have had an air bubble that finally worked itself out.

I really hope that's what happened. I did change the coolant a couple months ago when I installed new header gaskets and never really got a good, definitive burp out of it. I wouldn't be surprised at all if there was a bubble in there.

sireland67 said
Maybe the thermostat has not been opening all of the way, the extra heat made it open up??????????

That's another possibility I was considering. The Milodon units have a pretty good rep but I think that ALL thermostats are suspect.

Whatever may have caused the temp to drop 20+ degrees, I'm just glad that it did. It really would have sucked be forced to pull over on an on-ramp during heavy traffic and watch that Mustang slowly pass me by!