Looking for some info to help explain a whining noise, which started last winter, that I am hearing from the engine compartment on my 05 expdy (loud at cold start up and then varying in intensity mostly through the 1400-2100 rpm range). Serpentine belt and tensioner were replaced yet whine persisted; dealer said they troubleshot all possible issues (tran torque unit, etc; and discovered noise was coming from alternator. However, alternator was functioning 100%. I decided not replace (@ $275) because I didn't I trust the dealer diagnosis. As the weather warmed up (May) the noise went away and I thought maybe something had broken in or stretched out. However, as the temp has dipped below freezing now the whine has reoccurred.

Anyone have this problem or have any ideas? Thanks!

 

Ive heard of this problem before, I forgot what people said it exactly was but I think it was a cold pulley. I didn't make sense at first but then after looking into it thats what the problem was for some people. I never had this problem but I would also see if the power steering pump is making that noise, sometimes I heard ps pumps whine super loud when cold. I am not 100% sure on what your problem is but this is my best guess.

 

I had a screeching screaming noise a couple of months ago... at any speed, at any moment. Sometimes 9-10 times within 100 miles. And then... it went 2-300 miles without making a noise. Then it started again.... no one could figure it out.

Crossing my fingers ... noise hasn't occured in over 1000 miles now... who knows what it was ?!?!?!

 

I have had the same problem with my 03 every winter and I have had this truck since it was new. The problem is intermittent and never happened at the dealer. I have no idea what it is, but its seems to go away after about 5 minutes. Also, if i am driving and it starts making the noise, it goes away as soon as I release the accelerator. It sounds awful, but so far does not seem to be affecting anything. If anyone has thoughts on this, I'd love to hear about it.

 

The whining is no doubt a bearing issue on an idler pulley or a system pulley.

Tim

 

The squeal with my truck is in the drive train somewhere. You can put truck in neutral and squeal sounds the same.... even though engine went to idle.

Fortunately, noise has not returned and I've had it in all sorts of terrain, etc in the past few weeks. Crossing fingers it will never come back ! lol

 

Experiencing the same issue every winter here in Ohio with '04 Expedition. High pitch whistle coming from engine compartment. Can replicate over and over at 59 and 69 MPH on very cold days, usually under 25 degrees. Whistle stops under or over 59 MPH or over 69 MPH. Very puzzling.

 

My Navi makes the same type of noise when it is cold out (read single digit temps). Tonight it started making the noise (9 degrees temp) when we pulled in the driveway. Poped the hood - to darn cold and dark to mess with it, but did notice that if I put my hand on the air intake hose you could feel a vibration like a solenoid was opening and closing at a high rate of speed. As soon as I blip the throttle the noise (and the vibration) go away.

 

Yup...looking for answers...lots of opinions out there....I purchased my expedition new. For 5 years now, when the temperature falls below freezing their is a whining noise in a very tight range within RPM's. Engine can be hot or cold. You can hold the noise steady in the throttle, let off it fades away...speed up...it goes away......I dont remember if it occurs in park, but believe it does. If its 35 out, its totally quiet....vehicle has 87,000 on it....mostly highway, and is extremely well cared for and very very smooth. Everything on vehicle except battery and tires, is still original. Fluids / filters changes always on time or ahead of schedule. Any thoughts on troubleshooting, or fixes??

Thanks
Mark

 

I know you said that the belt and tensioned have been replaced....but I have seen this with a brand new belt. It goes away after the belt warms up and gets more grip.
Tracing the nose to the alternator is not uncommon because it has a high rotational load because of the heavy charge load when trying to recharge the battery right after engine start. It is also the smallest pulley on the engine. Because of this it has the lowest square inches of contact area, making it a high candidate for slipping.

If you didn't replace with a high quality brand name belt (Gates, Ford OEM, etc.) I would suggest you try a different one.

 

Were you able to figure out what your issue is? I have a 05' f150 stx with 124k miles on it with the same issue. Starting squealing when it got cold out and is really loud and annoying. It is only in the mid rpm range and seems to be worse when I am not accelerating hard. I replaced the serpetine belt two days ago with NAPA's $50 belt and it is still there this morning. I checked the two idler pulleys which seemed fine, but have not checked the tensioner pulley. I did take some emery cloth and scatched up all three pulleys in case they were glazed from the last belt.

Last week i did spray some wd-40 on the back side of the old belt and it did lessen the squeal for about 4-5min, but came right back and did not last. I need to get this fixed because it is realy loud, but i am strapped for cash right now due to a new addition in the family three weeks ago......repairs always have great timing!

I have been reading all kinds of forums and would hate to throw money at it without narrowing it down more. Hopefully some of this info helps you with your problem as well.

 

You need to determine if the noise is due to belt slippage or from a bearing. There are two different courses of action to repair either one.

 

I can't imagine that it could be a belt issue since it sounds exactly the same as before I changed the belt. No less and no more. I will try to pull the belt off tonight and check the idler pulley to se if there is any play in the bearing. Depends on if i can convince the wife to manage the newborn for a few more minutes........

 

There are 2 idler pulleys, plus the one tensioner pulley. Try to feel for roughness when rotating any of the 3.

 

Alright, it was a struggle and i payed for it, but i took the time last night to pull off the two idler pulleys and tensioner. One of the idlers had some grinding in it, and the other one just had a faint smidge. The tensioner pulley was pretty smooth, but when I spun it it made a faint almost squeeling noise. Since i had it all apart I decided just to spend the money and replace all three since the tensioner pulley made it seem like it was the culprit.

To my surprise it still isn't fixed. There is an aprovement though. It didn't seem to start right away when it is cold, but seemed to get worse when it warmed up some. It also didn't seem as loud as normal, but this was only during a 7minute drive to work. It is in the same rpm band of right before it shifts when accelerating easy. Doesn't seem to do it as bad when accelerating hard, but it can be held at a constant rpm.

Any more ideas? Everyone's help has been really apreciated. I'm hoping to not have to throw much more money at this without fixing it because my wife might possibly kill me (she doesn't go back to work until the begining of the year) so we are tight for cash this month. Thanks again.