On the way back from Columbus, the truck was running hot and I had to keep it under 65mph in order to keep it cool enough to get home. So I did some preliminary checks, make sure the coolant level is good, make sure the gauge is still indicating correctly, make sure timing was right, that the plugs look normal and that the lower hose was not collapsing. This all checked out, so the next best guess is the thermostat and it turns out it was the problem.

It was a Robert Shaw type Mr Gasket 4367, 180 degree with over 10000 miles but I'm not sure of the exact mileage because it looks like I did not record it. I replaced it with a Milodon 16406 mostly because the Milodon is made in the USA and MR gasket is Made in China.



I used a heat gun to heat them to about 210 degrees and here you can see how far it should open (right) and how far it was opening (left). The good one pictured (right) is actually a 160 degree that I got from Stewart components years ago. I think it will go in my "roadtrip spare stuff box" for next time since they aren't that easy to find. Even standard Mopar (same as the Y) thermostats aren't very common at the parts stores.



If it really matters to you, it looks like the made in USA component has writing on the side and a shorter copper dealamajig in the center and a stainless pointy end while the made in China component has no writing and a taller copper dealamajig with a brass pointy end. It matters to me, but who knows if that info may actually be useful.


Lawrenceville, GA