So recently my jeep has made this high pitch whine noise, kind of like a supercharger whine. It starts about 15 mph after the jeep has been sitting more than an hour or so and it is audible up to 50, and it gets louder with speed. I dont think it is engine related because i can slip it into neutral, rev and it doesnt change. only with speed. the wierdest part is this happens only the first time driving after it has sit. after i get it up to speed, hear the noise, i can come to a complete stop and it completely goes away. Only to return after it has sit for more than hour. I dont even know where to begin looking but i think it drivetrain related.

 

u-joints(drive shafts and end axles), hubs or brakes. All three can sound like that and fit your description. But i would tend to say more so the end axle joints or hubs

 

The double cardan joint in the front driveshaft possibly. Mine only does it when cold

 

today was above freezing and it didnt do it, so I think it is cold related. all front end components are new minus the driveshaft. I swear if the joint is bad thisll be my 2nd driveshaft within 6 months

 

Won't hurt to check the brake boost check valve for a crack or leak. Found mines to have a crack, it made a hight pitch sound also. Mopar wanted $18 for the valve and a 4 day wait, went to aoutozone and got a doorman replacement for $5.60 and did the trick. Also could be exhaust related, either manifold gasket or headers as per my research but hope not for you.

 

Post #1


https://www.cherokeeforum.com/f59/pr...-trick-231563/

 

LMAO nice Ken

But I know the centering ball in the front driveshaft likes to do stupid stuff like this.

 

Curious on what it turned out to be???

 

Sorry to revive an old thread. I'm also having the same issue, but it happens as soon as I start up the vehicle. I made a quick video so I dont have to try and describe it




Im pulling my hair out trying to figure this out. I dont even know if I'm pointing at the correct area with that video hahahah