Well... my truck was running great for about a year or so... and today I was driving it around, and it looked like it was going to rain, but it was hot out. So I turned on the A/C and I started driving, the compressor was engaging fine, then all of a sudden, I hear a clunk from what I assume was the compressor engaging then my truck's engine started whining. I wasn't going very fast, as I was in first just using the idle to propel me because I was on my work grounds and I can't go fast, for obvious reasons.

So I got home and let it cool, thinking it might have been a fluke or something... but nope, I cranked it over again, and at around the 1000-1200 rpm mark, she whines like a baby. I was thinking it could be something with the alternator, but it doesn't sound like it is coming from there. I used a long screw driver and put it up to my ear, but it's kind of hard doing that to certain areas of the engine for obvious reasons. It is way more pronounced when it is cold than warm.

I checked all the pulleys and accessories to see if any of them were hot, and they all felt normal, nothing hot enough to burn me. I did look at the belt carefully, and the top is kind of sticky/glazed. Not really sure if that would have anything to do with it.

I am also thinking it might be one of the pulleys or the actual tensioner. But I can't tell.

It's driving me nuts because the radio doesn't even mask it and people look at me funny as I drive by.

Any suggestions? I'm swinging it by the shop tomorrow and see what they have to say.

 

maybe someone installed a supercharger when you werent looking?

all jokes aside, my alternator makes a very quiet whining sound. could also be power steering?

 

Well, I brought it by the shop, and they took a quick look at it, and they told me to hold off until Friday... it seems like it is actually quieting down. But the pesky noise is still there.

I was also thinking the battery could be going bad too?

All in all, the truck is running great though... don't know what would cause it to all of a sudden make something go.

 

If the battery is getting weak, that could cause an alternator whine from the heavy draw to recharge it. Power steering pumps can also whine.

 

check your idler pulley and all the other accessories. Take the belt off and spin the pulley by hand.

 

power steering pump mine was doing the same thing took it to ford and they replaced the powersteering pump since the truck is still under warranty and problem solved. it would wine no matter what turning the wheels or just ideling

 

Well, an update...

I decided to change the belt, since I took it off to inspect the pulleys and accessories. I got a Dayco PolyCog belt. It's an awesome looking belt!

However, that still didn't fix my problem.

When I had the belt off, I spun everything I could spin and nothing seemed weird... other than the alternator had a *slight* resistance to it, and the powersteering had a *slight* resistance to it as well.

The fan, the tensioner pulley, and the two other guide pulleys all had great freedom of movement and they could spin with ease. There was a slight noise with the alternator, it sounded like a rubbing noise.

So I'm not really sure what it could be. I hate like heck as to start throwing parts into it when Ford can fix it for free. Bad enough I already bought a belt... but then again, it was a mod in some regard.

Added:

I was doing more hunting, and came up with an idea the possibly the pulleys could've gotten contaminated with something OR the pulleys needed to be cleaned. I read that brake cleaner works wonders on removing grease and other road deposits off of pulleys to allow them to have a clean surface. So I took the belt off again, and spray and cleaned ALL the pulleys and rechecked all of them. I then let them dry for about 20 minutes then put the belt back on.

However, I just got a hunch that it has to be the alternator... because it is more pronounced in that area. But then again, so are 2 pulleys and the tensioner in that same region.

Verdict: Still no change...

 

Did the tensioner itself have any type of wear on it? Did the old belt show any wear? Sometimes those tensioners and alternators feel smooth when turning by hand with no tension but as soon as there is a load they start screaming again.

I just replaced the belt, tensioner and alternator last Saturday on my wifes T&C van. I bought all 3 and replaced the belt and tensioner first. That didn't cure the noise so I replaced the alternator. Sure enough the most expensive part fixed it. The old alternator had no noise (was using a stethoscope) at all turning by hand.

 

No, the tensioner looked great. The old belt started to get glazed, but nothing overly special.

The alternator felt smooth turning it by hand, but it had like a rough noise inside of it. Nothing loud... but I was thinking about taking it off and bringing it by AdvanceAuto and have them do a test on it. That oughta bring out any noises in it.

Then again, the truck is under warranty, so I didn't feel like investigating it any further -- unless the dealer stiffs me... if they stiff me, I'll just taking the thing apart. Which I'll have all weekend to play with it.

 

just a question, but how many miles were on that belt?

 

~28k miles... but I do a lot of extended idling as well. So if you were to count the hours on the belt, it'd be in realm of 700 to 900 hours. I know for a fact there isn't more than 1000 hours on the belt.

But here's an update:

I decided to carefully monitor the voltage, and I noticed a lot of voltage swings. So I went out to Wal*Mart and bought a new battery. However, I didn't buy the same replacement size, I went with one that had 1000 CCA at 850 CCA @32F, which is supposedly designed for SD's according to the fitment guide. That battery ought to be able to handle my increased loads from my radios, lights, and more.

So I dropped the new one in, and hooked everything all back up, and started the truck... the whining noise is still there. However, the voltage readings were great! No more dips which I feel much better about because I can only imagine that problem could damage my radios or even the truck.

Did I need a new battery? My answer to that is yes. So I didn't waste no money there. Plus I wanted to upgrade the battery that was in there to handle the load, so no sweat off my brow on that one. I've already considered the belt and battery mods, because they are way superior than the factory components.

But I'm still intrigued as to what the heck that whining noise is. I can only say it has to be a pulley, tensioner pulley, or the alternator.

Oh, and just to let you guys know, it is NOT coming from the PS pump, actually, it's not even coming from that area, it is coming from the passenger side, right where the alternator, 2 pulleys, and the tensioner is.

So tomorrow is Thursday, I'm going to take the truck to work then drop it off so they can play with it on Friday and hopefully fix it for me.

I just got a hunch it might be the alternator. But I'll let them find it. It's making noises that it shouldn't be... Ford should find it. Unless... they try to tell me a noise that just appeared is normal, I'd make sure they would fix it.

So anyone else got any suggestions for me to try?

Edit:

Got another question... would a bad or problem-matic battery cause an alternator to fail?

 

Maybe you need a higher capacity alternator with all the electrical crap you have in that truck.........................

 

I ran it with anything other than the trucks original wiring connected -- no accessories were attached at all.

Besides, it does it even with all the stuff turned off. So it has nothing to do with load on the alternator.

My buddy thinks it might be the bearings in the alternator starting to go.

 

I tried to tell you that on post #8!

 

are you planning to leave a note under the hood for the technician?