Hi all,

Here is my dilema. Started a few months ago on my 2004 1500 V8 4.7L 2wd.

When I first start the truck up in the morning everything is ok. I put it in reverse and back out the driveway. Once I shift into drive I hear a high pitch squealing noise that changes pitch with the rpms. As the rpms climb the noise gets louder and higher. If I take my foot off the gas it may or may not stop. This doesnt happen every morning, but seems to be getting worse lately. The noise will stop usually after a few blocks of driving (30 seconds to a minute), and may reappear for a few seconds later on down the road. But after the truck is warmed up it doesnt seem to happen.

I have tried turning off and on the a/c and heat, putting the truck into neutral but there is no change in sound.

I figured it was a belt and had the belt changed out but that hasnt solved the problem. Had it into the mechanic twice but both times it didnt make the noise for him (ofcourse). He suspected a vacuum leak but couldnt find anything.

Any ideas or suggestions would be great! I leave for work early in the morning and pretty soon the neighbourhood is going to start pelting me with eggs!

 

It may not necessarily be a belt.. it could be any fixture running off the belt. Try and put a Steel tool on anything drawing power from the belt and put your ear to it. If you notice the sound peak at a certain fixture... you've found your problem.


Had the same problem in my BMW... thought it was the belt... then the Vacuum advancer, came out to be the alternator.

 

Problem is that it only does it for a few seconds and very rarely in park. I have tried jumping out of the truck and throwing open the hood but by the time I do it, it has stopped.

 

It could be the belt tensioner!!

 

hmm thats wierd. Mine was doing it in the cold/ startup and it lasted for a good 2 minutes. Wish it was going on for a longer period of time so at least you could localize it : / . Sounds like the only way your gonna catch it is if its on a dyno. Bring it to a garage with a dyno and see if the tech can find out where its coming from...

+1 on the tensioner as well..

Good Luck bro keep us posted.

 

Brought into the garage twice now. Even left it over nite once so he could start it up cold. Never made the noise for him. When yours was doing it did you ever find the culprit?

 

Well finally got diagnosed. Met the mechanic at the shop after leaving the truck there overnight. Took it for a spin and it made the noise. Threw it in park and it continued long enough for us to atleast narrow down the area. Got the belt off back at the shop and it appears to be the tensioner pulley. Also found alot of play in the water pump so that is going to need replacing as well. Quoted me $400 taxes in. I am going to poke around here on the site and see what is involved with replacing the water pump. Anyone tackle this before? The tensioner pulley should be farely easy....

 

Belt and tensioner are very easy. Water pump is also easy.

Tensioner is either P/N 53030958AC or 53030958AD

As for the pump, just take loose you upper/lower hose and get them out of the way, then take loose the clutch fan and the belt and simply un-bolt the pump and replace it.

 

Well well. After 5 months of noise free heaven its back! History - Replaced the tensioner and idler pulleys both. The idler was definitely done as it would barely turn. Also had the water pump replaced by my local mechanic (couldnt get it off without the spanner wrench) and inspected the old one - bearing was pretty loose. No squeaks or squeals since. Thought the problem was solved.....

Now its back again and has me scratching my head. Thinking towards the alternator maybe??? Any ideas would be a help.

Again it usually doesnt do it in neutral or park but rather in drive. Happens around 1700-2000 rpm and will stop immediately if I take my foot off of the gas and sometimes if I rev it up.

Thanks!

 

Sure its not the CAI making the noise when it is sucking air?