Hi everyone, newbie here. Just bought a new 4.7L Durango three days ago and am very happy with it thus far, however there is one thing that has me wondering. At startup there is a loud roar coming from the engine, sounds like a huge fan and when I give it some gas at idle and get off the gas the rpm's lag quite a bit. In a matter of about 30 secs the roar subsides to the "normal" fan noise and the throttle responds normally. I did a search and someone mentioned the clutch fan as a possible problem. There were only two posts and the last one was back in 2004. Can someone shed some light on this. Is this normal for the Durango or do I have a problem.
Thanks, in advance. I have to build my knowledge base on the Durango and Dodge's since I'm coming from a Chevy background.

Flea

 

Mine does it and I had a buddy that had a dak that did it. It's fine. Once you start driving and get it over a certain rpm or let it run it stops right?

 

Yes, it stops just like you say. I was just wondering what is causing it.

Flea

 

Nothing to worry about then enjoy your new truck and be easy on the tranny.

 

I'm enjoying it but you sparked my curiosity....why the comment about the tranny? Are they a weak link in the Durango? Don't scare me, I'll be towing a 5500 lb boat.

Flea

 

From what I have heard, a wise investment would be a tranny cooler (auxillary transmission oil cooler, they go in from of the raditor).
B&M makes them, or, you can pick up one at your local auto store. Heat kills automatic transmissions.
Also, when towing something heavy, disable Overdrive (so it won't shift past 3rd gear).
If you take care of your transmission (fluid and filter changes are recommended every 35,000-40,000 miles, and an aux. cooler will help keep the heat down), it will last.

 

When you cold start the, D the throttle stays open for a few seconds and it results in a very loud roar that lasts about fifteen seconds or so ... I noticed mine more during the winter. I beleive the explanation is that it helps build up power, but for the life of me i can remember exactly where i heard this info.

 

I have heard the tranny's are weak on Dodge and I was lucky enough to experience it for myself. I bought mine used with a little under 30k miles and at 35k I said bye bye to my tranny. $1800 later my tranny still gave me electronic problems. I had it in the shop about 13 times after the rebuild to work all of those problems out, usually weekly. I think they worked out all the bugs it hasn't given me any problems for over a month LOL. I'm at 41k now and took it on an offroad trip to PA without any problems through some nasty stuff. Also taking it out of OD and gettinig a cooling system on that tranny are good ideas for towing as stated above.

 

Okay, I found an explanation. I got if on a Ford Bronco forum. The reason for the roar (increased fan noise) at startup is as follows:

Q. My fan clutch makes a loud noise when started cold. Is that normal?
A. Yes, most fan clutches allow the fluid to drain into the working area when shut down. At startup it may take 1-2 minutes for the clutch to slow down.

The explanation came from the following website:

http://www.ford-trucks.com/lc/lc.php...com%2Ffaqs.htm

Flea

 

This has been covered before

https://dodgeforum.com/m_275409/tm.htm

HTH
Jeff