I have a mystery squeal that i keep throwing money at but wont go away. The squeal appears to come from a pulley or something in the serpantine belt system. it only happens when its cold, when im on the gas pedal and goes away after the truck gets warmed up. i have replaced all three idler pulleys and the tensioner. i had to the truck at a dealership for a week and they say they couldnt duplicate the problem. upon picking it up it was squealing when then they drove the truck around for me to pick up. it only did it for a second and they couldnt get it to do it again. thats a whole different story with them though. none the less the damn thing still squeals. i have a gator back belt that is about a year old. anybody please throw out some ideas before i burn this truck down and make an insurance claim!

 

alternator

the early trucks are known for this...there is even a TSB out for weird noises that the alt causes in cold weather.

 

can i replace just the pulley or do i have to replace the whole alternator?

 

you might be able to remove the pulley from the input shaft...but I doubt it

even then, I think it's a bearing issue. not a pulley issue.



if you do a search, you'll see what I mean. Every winter brings guys in with that strang noise.




sorry to say this, but it seems your only solution will be a new alt.

 

You should be able to remove the pully on the alternator using an impact wrench. I had an underdrive pulley for the alternator on my Mustang, took it to Autozone and they swapped them out. Don't know if that will fix your problem but it can be done.....

 

That won't fix it. The pulley just rotates on the shaft. The shaft bearings is what squeals. I had my factory alternator in my truck the last few weeks while I changed out the factory pulley for a overdrive pulley on my high output alternator. The factory one started to squeal just like you mentioned these last few days. I put my aftermarket alternator back in and the squeal was gone.

 

I got an aftermarket alternator from advance auto. gonna put it in on friday. hope its the fix! will post the results

 

Please do let us know if it solved your issue.
I have the EXACT same problem.
It annoys the sh*t out of me but quickly goes away once the truck runs for a few minutes.
Thanks.

 

Did this also affect the 05 trucks? My dads has started doing it, and I want to make sure it isn't anything bad.

EDIT: Saw the OP's truck in the other thread was an 05.

 

how much did the aftermarket alternator cost? mine is doing the same thing, mine started a while ago when i went hunting and used my truck as a snowmobile and a water raft worth it though....

 

It would probably be cheaper to find a alternator repair shop and let them fix it. Shoot they'll probably just spray some lube in there.

 

My 07 does this too, sounds like its comming from the alternator aswell..

so its not just the early models

 

well it wasnt the alternator. im embarrased to say....it was the belt. after throwing almost 500 bucks at this squeal it was the 35 dollar belt. i had a goodyear gatorback belt on for about a year....and only about 4,000 miles on it in that year. it was stretched about 1/2-3/4" compared to the new replacement. i thought there was no way it was the belt so i started replacing parts. so now i have new idler pulleys, new tensioner and pulley, a new alternator and finally a new belt. gatorback belt good for a year and 4,000 miles!!!!???? wont be on my vehicles ever again.

 

sorry to hear that, i guess i will try my belt and see if that makes a difference, what is a good brand belt though? Or just get the one from the dealer and have them throw it in there?

 

I dunno what kind of needle bearings for uses in their new alternators, but they stink!

I got a Napa new alternator for my truck, and it is quieter than stock! Even when I have all my lights on, radios on, etc... not to mention it is 1/2 the price of a Motorcraft Alternator.