The GM Thermostat Wrench is designed to work on GM 3.1 & 3.4 L V6 engines years 1994 to current. A common job on these motors is thermostat replacement. To do this you must remove the thermostat housing and in these applications the bottom housing bolt is almost inaccessible without removing other parts - until now. Our GM thermostat wrench with its unique shape and design will allow users to remove and install the housings in a fraction of the time it currently takes. The wrench is a 13mm,12 point with special bends specifically for GM V6 thermostat housings.