Thermostat Replacement on 3.4L: Nov 2014

Sometime during the month of November in 2014, I had to replace the thermostat on my 3.4L in my Chevy Impala. I'm not exact on the reason why I did so, but I have a brief memory or scare of the temperature gauge climbing well past the normal reading and up in or close to the red.

Sadly, these are the few pictures that I took. The throttle body assembly is shown in the left pic next to the Mass Air Flow sensor and rubber intake ducting. The thermostat housing is displayed in the pic in the middle with a closer view of it in the pic on the right.

The thermostat on a 3.4L lives down under the throttle body housing. When pulling the throttle body off, do note that there are two small coolant hoses attached to it that will need to be replaced because about the only way to get them off is to cut them with a utility knife. I believe the parts store sells a molded hose for the throttle body that is ONE piece which can then be cut in half and used as two (note: a person should be diligent in checking upon purchase).

The thermostat housing itself is made of aluminum and because of this, I caution anyone performing this task to use a torque wrench on these bolts upon installation of the housing over the new thermostat with rubber seal/o-ring. A long time ago, I broke an aluminum housing on a Buick Century with a 2.5L when I replaced the thermostat in that vehicle; leaving me to scramble for a used one at a salvage yard. Moving along, one thing that I really like about the 3.4 liter is the bleeder screw on the thermostat housing shown in the far right image.