Engine Bay Whine & Squeal

[zbeastburn]

Starting last summer I started having a squeal in the front of my engine bay. Sounded like the fan belt to me. I've had it in the shop SEVERAL times and they have replaced the belt and tensioner but it is still making the noise. Any ideas?
Also about a month ago my truck starting making a whining noise whenever I'd been running it and then shut it off. The service shop said it's my CAI releasing built up pressure but after having the CAI over a year why would it just now start doing this? Any ideas?

[CRIS PAYNE]

whining typically is rear end my friend I have already had mine swapped twice yes I said it twice both times it was a high pitch whine! Tell the dealer to crack the rear end open pull the pumpkin out and look at the gears! Bet thats what it is!

[zbeastburn]

I can't believe you have already had to have yours swapped twice. I will look into that. My one question though is how could the rear end be making that noise when the noise is definitely coming from under the hood. I mean the noise is so obvious there is no mistaking it for coming from under the hood.

[CRIS PAYNE]

i thought the same thing as well but they said it was the rear end i was like wtf??? I also had a cb boot break and they had to replace a halfshaft for the front dif check that also!

[Jeremy Breaux]

The rearend would not be coming from the hood. If it is, half the job of replacing it is already done because it is not where it should be. A high pitched whistle is your CAI. A whine could be an ac clutch or the tensioner is off alignment. try a little belt dressing on the belt. if it stops it is the belt rubbing across something like an off aligned pulley. If it doesn't stop or change then I would be looking at the ac clutch, alternator, Powersteering pump, ect.

[CRIS PAYNE]

You are wrong here Jeremy!!! Straight up beg to differ plain wrong!!! Cai whistles true sure does I have one and she whistles all day long!! Whine is front/rear end going out also! When mine was I could have bet a testicle that the noise was upfront!!!!! I looked and asked and kept taking the truck in but hey I come to find out that the noise I was hearing from what I thought was teh front was actually my rear end going out! There is a pin that slides in and out and it had gotten stuck and wore down causing some damage, the pumpkin was replaced and hey bye bye noise! It may be the belt and yes that would wine/squeak also but as many trucks I have had I can damn sure say and justify that a whine 9 outta ten times is front/rear end going out! That is a great indicator letting you know to check it before it checks you and just doesnt work anymore! Power steering pump is more of a grinding/squeeling sound mixed together.
It can be a number of things but hey grab your half shaft on either side of the truck and shake it, if it has play that can be a problem as well. I have had that go wrong also! If your truck is four wheel drive and you have used it a number of times that may have something to do with it.

Not trying to be a dick Jeremy but when you say rear end noise cannot be heard from the front, you are wrong I have two great experiences alone with the tundra! First hand happened to me! I went with the service advisor and when he said its your rear end I thought man hes crazy its teh frobt thats making the noise! nope it was the rear!

some indicators are loss of power, maybe a grinding metal to metal sound, and a whine from time to time. Let us know anyways, hey it can be your belts again or something who knows!

[Jeremy Breaux]

Sorry, My experience diagnosing and fixing issues like this across my last 15 vehicles tells me that it isn't the rear end. Beastburn seems to be an intelligent guy so if he says under the hood I will assume he did a check and narrowed it down to the engine bay area. Bryce's issue and resolution is proof of that. Also. The rear end doesn't whine when it is not moving.

[CRIS PAYNE]

I never said it did only when you give her some gas.

[Bryce]

my whine came from my power steering rack which i had replaced. it was the pump cavitating. not sure if that helps

[zbeastburn]

Thanks for all the input guys. I'm taking it all in and just walking through the process of elimination.
Here's what I have so far:
1. The whine is slightly there while going down the road, but it is at it's WORST WHEN THE TRUCK IS PARKED AND TURNED OFF.
2. The squeal only happens when my AC is blowing. I turn the AC off, the squeal goes away.
Again, thank you. I'm just very frustrated with the dealerships I have been dealing with. I tell them exactly what it is happening and then they come back with something different. I've had this truck in at least 6 times now for the squeal and three times for the whine. I mean come on, don't you think they need to get their shit straight. I'm just pissed that I pay all this money for a product and yet they have no idea what the hell is wrong with it. Just doesn't make much sense to me.

[Jeremy Breaux]

Squeek is the ac compressor. when there is a load on it the belt is slipping.
That means either the compressor is too had to spin or the tension on the belt is wrong.

[zbeastburn]

You see that's what I was thinking but supposedly I've already had the belt and tensioner both replaced twice. Something just isn't adding up and I'm beginning to get pissed.

[CRIS PAYNE]

Now that you mention it like your last post Im going to have to agree with Jeremy. Ac compressor, try before you shut the truck down turning off the ac see if the noise still comes when you shut off the truck, shut off the ac about three minutes before the truck use process of elimination.