98 Yukon 4x4 squeaky on cold start

[olliec420]

The 98 is doing great. Only issue (well besides the minor ignorable ones) is it has recently started squeaking on startup. See video. Anyone know what that is?

 

[Hoesgottaeat2]

Idler pulley, belt tensioner or serpentine belt.

Idler pulley you can remove, lubricate and reinstall. However I'd replace it soon after successful diagnosis.
Belt tensioner...same thing.
The serpentine belt is simple enough if determined it is the culprit.

 

[OR VietVet]

What @Hoesgottaeat2 said. Take the belt off and start. Bet the noise is gone. Spin the mentioned pulleys and see if they are smooth and no play, like they should be. If there is any roughness or play, replace them. But, the noise is not constant, so that leads me to a bad spot on the belt, glazed, that makes the noise every time it gets to a certain spot on whatever pulley makes it sound off.

 

[olliec420]

Will give it a go, thanks guys.

 

[YukonGTmaster]

If I was a gambling man, I would say "Belt Tensioner"

 

[ZEUS1]

my Wifes's 99 has the same problem, i have changed every pulley and the tensioner twice, and the alternator recently, and still have the squeak. It is annoying at idle but you can't hear it if your windows are up going down the road. It does go away once everything is warmed up. i am sure something will fail then i will really know what it is.

 

[OR VietVet]

my Wifes's 99 has the same problem, i have changed every pulley and the tensioner twice, and the alternator recently, and still have the squeak. It is annoying at idle but you can't hear it if your windows are up going down the road. It does go away once everything is warmed up. i am sure something will fail then i will really know what it is.

It is very rare but I have ran across where a seal will have a squeak noise till heat builds in it. I have found noises at the rear main seal and the harmonic balancer seal.

 

[Hoesgottaeat2]

...but you can't hear it if your windows are up going down the road....

Or turn the radio up if the windows are down...

 

[the 18th letter]

After letting my 99 sit for a year I would have a similar sound on startup for about 2 months after I put it back on the road. Sound is gone now and I’m not sure what it was. If it’s been sitting, it may work itself out.

 

[Hoesgottaeat2]

The 98 is doing great. Only issue (well besides the minor ignorable ones) is it has recently started squeaking on startup. See video. Anyone know what that is?

Have you confirmed you don't have a weeping water pump? That could be a culprit too, in my experience.