DML FAQ : Engine : How do I change my thermostat?

How do I change my thermostat?

From Dester:

For the 3.9L V6 and 5.2L & 5.9L V8s:
  1. Remove the upper radiator hose
  2. Take the serpentine belt off and take the alternator off (optional)
  3. Loosen up the 2 bolts on the t-stat neck. (at this point, you'll notice coolant leak down your block, have a pan underneath to catch that coolant)
  4. Take old stat out, clean gasket off the water neck
  5. Put the new thermostat in and install the gasket on the water neck with a thin bead of hi-temp RTV on each side.
  6. Put the 2 bolts back into the hole (get a magnetic tool picker-upper, because you'll more than likely not be able to fit your hands in there and will drop the bolt in a place you can't reach)
  7. Replace alternator, belt and radiator hose back on
  8. Refill your radiator. 1 container of antifreeze and 1 container of (distilled) water should be more than enough

Jon Steiger has an illustrated guide for this as well

Contributed by: "Dester", Jon Steiger
Last updated: Thu Mar 28 19:19:40 2002