Mystery "Belt" Squeal: What is it?

Hey guys,

I have a 2010 Sport with 108,000 miles on it that I bought used about 2 months ago from a dealership that provided a 3 mo. warranty. I noticed a light squeal when driving that resolved itself quickly the very first week. I didn't think much of it at the time. As the weather has gotten slightly colder, I began noticing it more. It only seems to do it while in drive, not idling, and within the first few minutes. If I'm driving through town at 25mph, it's slightly audible and stays pretty consistent in noise. If I accelerate it gets louder. If I come to a complete stop, it typically resolves itself and the noise is gone for the rest of the day.

I took it to the dealership and they switched out the serpentine belt 2 weeks ago. All seemed fine for a week. The noise is back again. I told them to check the idler pulleys and tensioner itself as it went in again for service of this issue. BTW, a FORD dealership is looking at this issue; I may need to take it to Toyota myself. They said they couldn't find any play in the pulleys or tensioner, put the belt back on and sent me on my way. They also said they couldn't replicate the squeal, which I assume means they didn't drive it, as I had requested, first thing in the morning (I left it with them overnight). As soon as I drove it home, it did it. Any ideas what the heck it is? Sucks to have just spent 20 grand on this thing and to have an issue like this right off the bat!

How do you suggest they diagnose it (or pinpoint the source) if it stops making the noise as soon as the truck stops moving or is shifted into Park?

Thanks for any ideas!

 

ive kinda delt with this for a while.. haven't truly found a fix.. But.. I fought it and fought it for several months last winter. went through several belts. cleanings. parts, was about to replace the water pump. Nothing made any sense. Running a gatorback belt now.. still did the same thing a week after install. started squeelin. A neighbor told me to use baby powder on it. did that. Worked great for a while. Every time it made any racket id hit it with baby powder. it kept going longer and longer til needin repowdered. as temps went up, I never had any more issues. hasn't had a problem all summer. it would squeal a little here and there if it got wet.. But that's it. Now temps have cooled again.. still no issue.. in short, what I'm telling you is.. I HAVE NO CLUE! lol. try dousing it with baby powder

 

1st rule, never go to the dealership for anything. we have a mechanic shop in NY and we fix a lot of cars for major dealerships. they have bunch of imbeciles working there. you cant always feel the play in the tensioner. that thing spins at a high rpm and even a hairline vibration will cause it to squeak sometimes. or if the bearing is slightly worn it will squeak which cannot be felt by hand.

 

I'm thinking wheel bearings or brake pad dragging if the noise stops when you stop driving.

 

rev the motor hard a little in part and see what happens

 

Trust me, I didn't want them to look at it, but it's under warranty. I may start with a tensioner replacement and then go from there.

 

When in doubt, use baby powder.

 

thanks, I'm pretty certain it's belt-related or something the belt attaches to due to the sound - pretty standard belt squeal.

 

One trick that can be helpful in pinpointing a noise is to use a piece of hose or pvc tubing, maybe 2 feet by 3/8". Melt one end so it is smooth. Stick the smooth end in your ear and direct the other open end around the area where the sound seems to be coming from. When the open end of the hose gets over the source, it will sound much louder. For more subtle noises, put an ear plug in your other ear. I keep a piece of this tube in my tool box. Best 50 cent tool you can buy. It works like a stethoscope, but does not require contact, so it is great for probing fast moving parts.

 

If the tensioner is OK otherwise, just replace the bearing; the bearing size is 17 X 40 X 17.5 . I put a Nachi 5203-2NS bearing in mine.

Here is another way to pinpoint bearing noises. Dude is a good mechanic and his name is Eric, but not Eric the Car Guy.

https://www.youtube.com/watch?v=fHtLH_m9gN4

 

Thanks for the tip. I can try this if it continues to squeal when the truck is not moving (so far, it only does it while the truck is in motion).

 

Thanks! Watching it now.

 

@Redmann

 

As @Chuy suggests, this is not typical of belt noise.

If you rev a bit in neutral, parked, does it do it?

Does it do it with the AC off?

If only while in motion, I'd be looking elsewhere.

 

Thanks man! I tried washing the front of the engine with a garden hose, high pressure nozzle, and hot water while I was at work the other night. It was suggested that I may have dirt in the pulleys because of the lake we went through at the very end of sunday at AOAA.

The garden hose didnt work. I was GOING to take the belt off and see if I can pinpoint the pulley, but I like what the guy in the video does. Thats a great tip.