I don't remember where I saw this, but there is a t-stat available for the LS4, I believe it was a 165 deg but am not sure. In the same place it was discussed that the LS4 t-stat is unique from the other ls engines. The bottom line is since I was not smart enough to copy or save the info, does anybody else know about the LS4 t-stat...how and where, to find one??? Please help, sorry for my ignorance.

 

I believe a t-stat for a LS2 will work on a LS4.

 

I used a 160* Thermostat from a 06 GTO. Worked like a charm and only cost about $12. I also added a bottle of Royal Purple coolant cooler or what ever Royal Purple calls it and bewteen the two the car seems to get cooler after warm up much faster than stock. Now all I need is a damn PCM flash so I can have the fans turn on at a lower temp than stock.
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