Overheating my 1999 dodge durango over heats when i trun on my ac

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

sounds like you need more antifreeze , make sure fluid is at proper line on overflow tank

as for noise will have to inspect under hood,could be fan or belt or pulley ,water pump .these are some things it could...My suggestion for overheating is replace thermostat. If your car has electric cooling fan then it may not be working..turn defrost on and if fan kicks on then fan motor is good..Now this does not mean that fan is working properly because fan is controlled by heat sensor switch that kicks fan on when motor reaches heat range......Things i would have checked....hope this information helps and good luck and Please rate my post...

I had this problem, I needed a new trun signal relay switch, and that solve my problem.

Hello, seber5 and thank you for asking your question on Fixya!

Here is a simple process that will walk you through a few steps that will pinpoint the overheating problem on your 1999 Dodge Durango, without even using any tools. It has helped millions of people, and I am certain that it will help you, because I wrote it for people in your exact situation.
How to diagnose your overheating 1999 Dodge Durango

Get more great money saving tips and tricks about your vehicle from: twitter.com/acoates23234

Thanks for the vote, and good luck!

Hello scottbutler and thank you for asking your question, on Fixya.

Here is a simple process that will walk you through a few steps that will pinpoint the overheating problem on your 1999 Dodge Durango, without even using any tools. It has helped millions of people, and I am certain that it will help you, because I wrote it for people like you. So here is the link:
How to diagnose your overheating 1999 Dodge Durango

Get more great, money saving, tips and tricks about your vehicle from: twitter.com/acoates23234

Thanks for the vote, and good luck!

It's a big job. Drain the coolant down, recover the freon in the ac system and disconnect the lines and heater hoses. Lower the steering column, remove the instrument panel assembly, remove the heater housing. Split the case halves on the housing and there you are. Usually around 500 to 700 dollars at a dealership.

theres a sensor to open the right vent for the ac try flipping
the switch to heat to ac if this doesnt work than you will have to take to a dodge dealership

Bad NEW thermostat? I had the same problem on my first generation Dakota. The problem for me turned out to be the DODGE thermostat I used to replace the old Dodge part. I went and got a Stant from local auto parts store using the standard temperature spec and quit shivering the next time I drove it. I hope that helps!

The dodge durango thermostat called for by the dealer is at the temperature of 192 you can solve this problem very simply by instaling a 160 thermostat that can be obtained at any parts store