Chrisreyn

In the last week or so, Ive noticed a dry-bearing type squeal from under the truck. It sounds like a piece of tin flapping in a high wind or a bearing running dry sorta sound. It is only there between 30-33 mph, and again at 40-45 mph, close to the tranny shift points. The tranny was gone through last summer By John over at Floor-It and is driving fine, fluid level is good and running a little on the cool side if anything...
The noise is not there when idling in park, but IS when idling at a red light or in gear...
Looking around under the beast, I noticed that there is a strap of some sort similar to a zip-tie that appears to have broken on the carrier bearing..
any thoughts or ideas, ?
Does it sound liek I might be on track suspecting teh Carrier, and how do you check one?
How hard is it to replace??
Thanks guys!!

ofcmarc

Long time no see Chris.

Could definitely be related to the strap thing. Might be catching a harmonic freq at certain speed causing the noises. Carrier Bearing isn't too bad to replace. Really pretty straight forward just make sure you get it centered when you put it back together or you'll have driveline vibrations and chew up u-joints.

BearKiller

No part of the carrier-bearing is moving, unless the truck is moving, so it couldn't be making a noise when sitting still.

12valve@heart

Agreed. If it happens when not moving, it won't be the carrier bearing.

My guess is that you have a shield or line that's vibrating at certain RPMs ("between 30-33 mph, and again at 40-45 mph, close to the tranny shift points") and when idling in park. Look for lines that are close to the frame or loose heatshields. My valvecover cover plate rattles at certain RPMs even so determine what part of the truck the noise is coming from and then track it from there. Could even be a loose baffle in the muffler (if you still have one). Mine did that for a bit too.

unixcowboy

That piece of metal you're referring to is the housing the carrier bearing sits in.
I had an '81 gasser that the mount rusted out at the frame and it had that little metal strap flapping in the wind....
If it's the carrier bearing it's in real bad shape because the bearing shouldn't turn in the mount....BUT - that strap will vibrate when the truck is not moving.

big stinky

Flexplate?