Hello Dodge Fans, I've had my 2000 4wd Durango for 9 years. When it starts getting cold out my Durango makes a strange whirring noise as I am driving for approx. the first 1/10 of a mile. At first I thought it was the trans slipping, but the tach indicates different. I thought maybe it was a fan or something of the sort. I am unable to diagnose the problem. Has anyone experienced this?

 

Welcome to DF. Moving to the correct section.

 

Most clutch fans engage fully for the first min or two of use. Odd that you never noticed before. You could just open the hood and watch listen too as you goose the TB.

 

The OEM clutch fan on mine would only do the jet taking off thing when it was cold, then the aftermarket one I put on afterwards would do it everytime I started the engine. Supposedly the mopar clutches don't do that.

 

Thanx for the Info. I did check the clutch fan,and yes it functions the way it should. But it does seem to hesitate a little bit until the whirring stops, and why does this only
happen when it's cold - about 45degrees F? Like I posted earlier, this has been an issue since I bought it 9 years ago. I keep an eye on all my fluids (tranny especially) and seems to be fine. If I didn't have a tach I would swear the tranny was slipping! Thanx again for the Info. I appreciate your knowledge. Also I would like to add the fact the I really have NO clue what I'm doing on D.F. Very new to the whole Internet thing.

 

This isn't really an issue, it just how the viscous clutch works. It has fluid in there that's density changes as it's temperature changes. When it gets hot the makes it engage more aggressively which spins the fan faster to bring the engine back to normal temp. Once it gets back to normal temp it spins slower. I'm guessing that when the fluid gets to ambient temps which are very low (compared to the 190 or so it's designed to maintain) it kind of gels which also makes it engage more until the engine warms it up some.

The reason it feels like it's being held back is that when its engaging the fan fully it's facing a ton of resistance against the air, so it's taking a lot of power to move the fan that would normally move the truck.

 

Okay, I just went out to the local store, the Durango has not been running for at least 6 hrs. NO whirring, NO hesitation. Last week my heater core started leaking on to the passenger floor mat. I used 8oz. "K-SEAL" and it seemed to do the trick, now I noticed leaking on the mat again. I'm not getting any fogging on the windshield,nor are my rubber heater hoses leaking.This wouldn't have anything to do with that noise, Would it? Please excuse my degree of Ignorance. I have 3 sons and work on their cars all the time too.I get to where I don't remember which vehicle I'm dealing with at times.

 

It wouldn't surprise me if there was some kind of residual heat still in the clutch keeping it from engaging so much (physics can be a mystery).

As for the heater core leaking that wouldn't have anything to do with it. This whirring and holding back on the engine is entirely normal for a viscous clutch fan. And just an FYI that leak sealant stuff is a bunch of garbage that'll probably do more harm than good (clogging up things, etc). If it is in fact the heater core leaking, you should just go ahead and replace it. If the fluid on the floor smells sweet, it's antifreeze.