Belt squeal/chrip noise.

[AZFX4]

Got a question.

I have a 2003 F150 FX4, 5.4 with CAI and Exhaust and the Gryphon. I haven't driven my truck much lately since I installed my Gryphon, but I only made 4 runs with it where I was ON the gas. Today I went for a drive and my first attempt at stomping on the gas and seeing what she has, when it hit 45mph and shifted I heard a squeal sound. I figured it has to be the belt? I've heard about the belt like squeal/chirp before on another forum. But never read up on it.

Then again I was at a light and stomped on the gas and it hit around 45mph when it shifted and I heard the chirp sound. Did it a few other times also when stomping on the gas.

I never went over 55mph because of the speed limit but getting up the speed it did that squeal/chirp sound which to me sounds like the belt. I asked a buddy he said it might be my tranny? But it doesn't sound like it? Another buddy told me my belt is likely bad and needs to be replaced?

Any adivce? Or why now I hear this squeal/chirp sound? It only happens when I hit 45mph when it shifts into 3rd. I haven't had the oppurtunity to stomp on it and go much faster than 55mph so I don't know if it does it at higher speeds?

And this squeal/chirp has just started since installing the programmer.

Thanks for any help. It's appreciated.

[Jackpine]

I feel certain it's the belt. I have the same thing, on the 2-3 upshift. Bill has altered the torque reduction, line pressures and clutch engagement delays, so there's a bit of a "hard" engagement there. The engine's spinning high before the shift and then the transmission drags it down abruptly. All the other "spinning things" have to slow down abruptly too and something "slips".

I doubt it hurts anything, but if you are bothered by it, the Gatorback belt has been recommended as a cure. I also imagine Bill could "tune" thins belt slip out. I don't feel either are needed.

- Jack

[88Racing]

+1 on the gatorback belt from me too!
The squeal is the side effect of the serpentine system design. If you do go with a gatorback belt and the squeal persists/continues a heavier load on the tensioner would be more desirable than to try and tune it out.
On my truck the gatorback has definately helped!

Be safe

Lars

[AZFX4]

You guys rock. I figured it wasn't anything serious, I was just curious and didn't want to snap my belt!

Yes, gatorback belt is on my list. Seems like it's the most highly recommended belt out there.

Thanks!!!!

[Desert Racer]

I too have this noise, hoping the under drive pulleys and gatorback belt will stop this.

[88Racing]

Originally Posted by Desert Racer

I too have this noise, hoping the under drive pulleys and gatorback belt will stop this.

I still experience it somewhat mainly at night with the lights on and ac when I'm matting the pedal!
The udps system has really put some extra pep in the truck.

Lars