Yeah, changing that thermostat isn't too bad. The hardest part of changing it out for me was getting the spring clamps removed and put back on the two hoses. I don't know why but they fought me pretty good.
You'll need a ratchet and some extensions, the 8mm socket (short or long) and a pair of pliers (needle nose, slip joint or channel locks).
Here's what you'll need to do:
1. Drain all of the coolant via the valve at the bottom drivers side of the radiator. That will take some time.
2. Then remove the electrical connector from the thermostat.
3. Then remove the spring clamps from the hoses on the thermostat.
NOTE - I remove my power steering switch connector wire for a little more hand room.
4. Then remove the three bolts holding the thermostat on and pull the thermostat out. I like to use a couple of extensions on my sockets to make removing the bolts easier.
5. Now ensure the new thermostat has a rubber o-ring and install it.
6. Reattach the two hoses and their spring clamps.
7. Reconnect the thermostat electrical connector.
8. NOW...take a moment and remove the upper radiator hose from the long metal tube that it's attached to. Check inside that metal tube to see if it is rusty (see below). If it is then that will cause problems. I suggest this because I had large chunks of rust lodged in my water pump/thermostat area of the engine block because of that steel tube. If that tube is rusty inside it will need to be replaced. If it looks good then reattach the hose and clamp.
9. Then refill the cooling system with the coolant.
10. Finally, start the truck with the coolant tank cap off and let it idle for about 15 minutes to burp the air out of the system all the while checking for leaks at the thermostat or hoses. Once it looks like most of the bubbles, burping has stopped and there are no leaks then put the cap back on and stop the engine. Let the truck cool all the way down and then check the coolant level and top it off if necessary. Then take the truck for good drive.
This was my tube. The entire inside was coated in a thick, flaky rust.
Oh, and this is the correct burping procedure should you want to try it. I really don't think it's necessary though. But it's good to have it just in case.
1. Fill the system through the degas bottle cap to the max fill level.
2. Start the engine and run for approximately ten seconds at 2,500 rpm to prime the heater circuit then turn the engine off.
3. Top off the coolant level to 0.6 inch above the max fill level.
4. Install the degas bottle cap.
5. Start the engine and hold at 2,500 rpm engine speed for approximately eight minutes until the thermostat opens.
6. Maintain 2,500 rpm engine speed for an additional three minutes.
7. Increase engine speed to 4,000 rpm and hold for five seconds.
8. Return engine speed to 2,500 rpm and hold for an additional three minutes.
9. Repeat the previous two steps.
10. Stop the engine and check for leaks.
11. Verify correct fluid level after engine cools for 20 minutes. Top off the degas bottle to "max" line.