I need to know about what kind of radiator for my 1999 Dodge Durango

Check for a clogged radiator. Also check for proper fan operation. Do not mess with the cap. That has nothing to do with overheating.

William, 1999 Dodge Durango, years for drivers door interchange are 1998 to 2000. "I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."

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remove the lower radiator hose it's safer than breaking the drain plug

make sure the engine is cooled off first

Both radiator hoses,top and bottom will be hot.If not recirculating then one hose won't be hot.

Did he flush the radiator? If not kindly ask him to flush the radiator and then refill it again.

Antifreeze is only for the radiator, does not affect the air conditioner, make sure you have the setting on cold, if it is still hot than take it to your local air conditioner re gas station, most auto electricians do it, dealerships usually send them out which you end up paying extra for!!! You just need a re gas in your air conditioner.

bad heater core. usually underneath the dash

Hello lennroi: My name is Roger and I will answer your question for you. If you follow the upper radiator hose down to the top of the engine. You will find the thermostat. This is in a hole behind the A/C compressor.It makes no difference if you have a 3.9,5.2 or 5.9 engine. They are in the same spot. Should you need further help just ask. Please rate the answer. This way I know your answer was helpful. Thank You for using Fix Ya.Roger

Yes. They should both be 46RE transmissions and the bolt patterns and the plugs should be the same.