The gasket on a thermostat for the 2002 explorer is a rubber ring instead of the usual gasket,is this correct?

There is a gasket on the base of the housing, the housing you speak off has the sensor and a heater hose and bolts to top of the intake and also hold the thermostant, this housing does contain a rubber molded gaske, i have replaced a few of these, heres the problem i have run into a couple where the plastic was eaten away in the area that holds the gasket in place. if you remove it you will see a groove that the gasket sits inside of, if the groove is broken then replace the housing but if its good then all you need is the gasket, you will need to ask for thermostat housing gasket to engine intake, this gets confusing to a parts person as they may think you are asking for the thermostat gasket, also in the rear bottom of the housing theres a hose connected to the housing make sure thats not your leak, the hose may also be leaking. good day

Buy a can of permatex gasket adhesive. Spray dome onto the gasket, thermostat housing and thermostat (make sure only to apply to where the gasket contacts the thermostat) and let it set up. It acts as a contact cement and will make it much easier to install your thermostat.

COULD HAVE DAMAGED RUBBER O RING TIGHTEN TOO TIGHT OR REUSED THE OLD ORING WILL CAUSE LEAKING.IF YOUR THERMOSTAT HAS PAPER GASKET INSTEAD O RING. YOU NEED TO PUT SEALANT ON BOTH SIDES OF THE GASKET.THAT WILL KEEP IT FROM LEAKING.IF YOUR VECHICLE HAD A RUBBER O RING AROUND THERMOSTAT REPLACE WITH NEW O RING DONT PUT PAPER GASKET IF YOU HAVE THE O RING SEAL.THE O RING DOES THE SEALING NO NEED PAPER GASKET.

That depends if the problem is with the rings or the valves or the head gasket.

Rings == engine

valves == valve job (remove both heads and take to a machine shop don't do just one)

Gasket == replace head gasket on that side.

bubbles indicate a blown head gasket :-(

Use what Chrysler parts guys gives you instead. Factory parts always work better

IF O - RING STILL LEAKING YOU COULD OVER TIGHTEN CRACKED IT.NOW FORD V6 USES THERMOSTAT GASKET WHERE YOU PUT RTV SEALANT ON BOTH SIDES.BUT IF USING O - RING IT SHOULDNT LEAK NONE.THE DRAIN PLUG NEEDS NEW O RING.BECAUSE IT CAN BE SCREWED ALL THE WAY OUT REPLACED. IF DRAIN PLUG DONT HAVE O - RING YOU CAN USE THE PLUMBERS WHITE TEFLON TAPE TO SEAL THREADS FROM LEAKING COOLANT.

It should be a rubber ring that actualy stretches& goes around outside edge of thermostat.

Is the thermostat the correct temperature rating. It should have a temperature listed on the thermostat, and does it fit the cavitity the old one came out of.
If the answer is yes then its a matter of the correct gasket. Call the dealer and ask them. Remember sometime the manufacturer change certain parts
they are not required to tell anyone they had. You might be getting an upgrade (as long as it fits the cavity for the thermostat.)
If the rating on the new thermostat is different from the old one and it doesn't fit the cavity then bring it back and show the dearler what came out of the vehicle . The same with the gasket.

remove the air intake that is on top of the radiator with a 10mm socket then the large hose that goes to the engine is where the thermostat is housed. Unscrew those two bolts which are 12mm and pull out the old thermostat and rubber o ring gasket. Make sure you put the gasket on the new thermostat good and line it up then reverse the last steps til its back together