Squeaking under hood

[tucker0104]

I can't tell if it is the tensioner pulley or the alternator pulley. Obviously, it is only when the truck is running, I already replaced the belt. I spun the alternator pulley when it was off and it squeaked a little bit. It almost sounds like two metal tools tapping. It isn't bad yet but wanted to already have a new pulley on hand for when it does. Does anyone recommend a certain bran of pulleys?

[White95f250]

Just replaced my idler and tensioner pulley. I had a random squeak then when I was driving to work last night it was a bad grinding noise. It was the bottom left pulled giving completely out. No bearings left. This was caused from the tensioner becoming bent. I bought a new one and it didn't look the same because it was a "fix" for better performance so it was longer. Bought two pulleys and the tensioner. No more worries now. Replace it asap though

[Aaron Berk]

Get an automotive stethoscope, you can pinpoint just about any noise. The cheap ones from Harbor Freight work just fine for diy use.

[Nashotah7]

Tensioner pulleys do like to blow apart, three or four of them here. Also I would check the vacuum pump.

[Maverick1701]

Originally Posted by Nashotah7

Tensioner pulleys do like to blow apart, three or four of them here. Also I would check the vacuum pump.

yea I had a squeak I couldn't locate....until one day I was driving and pow there goes the vacuum pump.

[backwoodsboy]

X3 on the Vacuum pump. I had a squeek a few weeks back...until the pump exploded on me. Shot the rear seal out, covered my valve covers with brake fluid, and destroyed a perfectly good belt.
Might as well replace it before catasrophic failure. No sense chewing up a $50 belt when the pump only costs $120.

[marine5811]

Just take a roll of paper towels or toilet paper (preferably just the empty cardboard roll itself) and put it to your ear and aim it at your pullies one by one. That will help you narrow it down. Works just like the auto stethiscope but you probably have paper towels laying around already.