Why does my 05 Durango emit a high-pitched whine when the engine starts?

I have a 2005 Dodge Durango, 5.2 liter hemi engine, 135,000 miles. For the last three months the car has emitted a high-pitched whine when the engine starts, while the transmission shifts through the gears, and while the car is at speed. The tone remains the same as the car runs, but it seems liked to the engine revs as the transmission shifts. A very reputable mechanic has tried to find the source without success. He’s run all the diagnostics, and used a stethoscope. He checked the alternator and the power steering pump and replaced two belt pulleys, but the whine is still there. He so far has not been able to locate the source. He says he’s heard the same noise on a couple of other Dodges or Jeeps with the same engine. I’d like to know what’s causing this whine and how to fix it.

“The tone remains the same as the car runs, but it seems liked to the engine revs as the transmission shifts.”

Please rephrase

I had the same problem with a 96 Dodge van with the 5.2 liter engine. after several fixes, a new belt stopped the squeel. BTW is it truly a “Hemi”?

The 5.2 liter is not a hemi, it is the redesigned 318 cubic inch V8.

Have you checked your power steering fluid to see if it’s low? I know you say a mechanic checked it, but I’d look at this first. Otherwise I’d suspect a problem with the pump in the transmission.

My mistake. The engine is the 5.7 liter hemi. The whine seems linked to the transmission in that the tone changes as the transmission shifts through the gears. But on the other hand, it’s detectable as soon as the engine is started, while the transmission is in park.

I am on board with Elly, it needs a new belt, it has been how long since it was replaced? If that does not work a piece of heater hose one end to your ear and the other used like a stethascope can help locate the source ie if it is a tensioner, alternator etc.

It could be a vacuum leak. First check the HVAC controls and see if you can redirect the airflow by the different positions on the control panel, i.e. dash vents, floor vents, windshield defrost. If that does not work, the the leak might be in the heater box where the blend doors are located or in the control panel.

Otherwise check all the vacuum hoses on the engine. Lastly, check the intake manifold gasket.

I appreciate all the comments on this thread. I’m only able to get on this page occasionally because of my work schedule. It looks like the consensus is in the direction of a belt problem or an HVAC problem. I’ll check both.

Vacume leak or maybe y our Power Steering pump is whining due to low fluid level or air in the system due to a leak? But PS pumps are known for whining a lot Check out the possibility of the vacume issue and or the PS pump… Could be?