magnetized

iTrader: (5)

Truck's a 99 4.8L with 99,000 miles on it. At startup there is a high-pitched sueak/squeal that lasts until the truck warms up then goes away. I'm thinking it may be one of the pullies that needs to be greased (hopefully not replaced ) any thoughts?

trever1t

iTrader: (14)

Belt slipping- try some dressing or replace,
Water pump?

BlackLM7

Belt possibly? Does the squeal get louder when you rev the engine up?

CHEVY6000VHO

iTrader: (2)

It's normally one of the idler pullies or old worn belt.
The idler pullies are not greaseable. They have a sealed one time use bearing pressed into them.
Pullies aren't too much.

Jim

magnetized

iTrader: (5)

The noise does get worse as the rpms go up. Thanks for the info, I'll try the dressing first

budhayes3

iTrader: (19)

I had the same problem a few years ago, turned out to be the upper adjuster pulley...the part was less than $40 from the dealer from what I can remember.

fake_usa

mine does that when it's very damp out..