CUCV thermostat vs HMMWV thermostat

[shotty]

Getting ready to do a whole bunch of cooling system upgrades and repairs and one of the new parts is a HMMWV crossover. The one I ordered is basically a brand new take off and in excellent condition. The thermostat part number is 12559337. The CUCV thermostat that I ordered has part number 14077122. I've attached photos of both. The CUCV thermostat is all brass, the HMMWV is steel with a brass hockey puck coated in rubber.

The CUCV thermostat has a small air bleed hole on the edge which you can see as a small bump on the radiator side of the thermostat. The HMMWV thermostat has three little holes towards the center with jiggle pins in them. According to the internet, they both open at the same temperature. I wonder why they changed the air bleed mechanism later on.

Anyways i thought this was interesting and wanted to share. I'll keep the HMMWV thermostat as its basically brand new, just in case.

 

[MarcusOReallyus]

Just different styles, I think. The two things that matter are the temperature, and the flow. There probably isn't a dime's worth of difference in how they will perform.

 

[Keith_J]

Local parts store quoted me $48 so I searched based on gm part number from -24 and got it online. Looks like a HMMWV type. The rubber is a positive seal element. It has the purge check valve jingle thing. We shall see how it lasts.