Making noise - driveshaft support bearing?

[midnightrider78]

The fun never stops! LOL
I have a 1972 C20 402/TH400 2wd with camper pkg and rear leaf springs.

Last week, after a couple trips hauling cars, I unhooked the trailer and noticed a rubbing/grinding noise when I drove away. It only makes the noise when the truck is in motion. There is no noticeable vibration, just the noise.
At first I thought it was the brakes but the pads and shoes all appear to have 10k or more left in them.
So, I'm crawling around underneath the truck looking for something that may be out of whack. I just happen to push on the driveshaft near the center support and it moves close to 1/2 an inch. So is that what's making the noise?

Also, if that is the problem, is there a way to know which bearing size I need before I dismantle it?(since I will be working in the driveway)

[Wrenchbender Ret]

Some movement is normal & nessesary. T he best way to check the brg. is unbolt the carrier from the frame, drop it down a little & spin it. It should not make any noise. A good parts man can get the correct on from the application.

[demian5]

Or, just spray with white lithium grease and see if the noise stops.

[bill3rail]

I recently needed to replace my support bearing. Similarly, I had a metal to metal scraping sound. Went underneath and the rubber was worn out. I dropped off the shaft at a drive shaft shop and he replaced all UJ's with new with zerk fittings, hanger bearing and balanced it.

Obviously, I could have installed the UJ's and hanger bearing myself but he had it done in less that two hours with balancing so I was quite happy.

Bill

[bill3rail]

Originally Posted by demian5

Or, just spray with white lithium grease and see if the noise stops.

I put red grease on mine to stop the noise until I got home and remove the shaft.

[HO455]

I would put it up jack stands and get a trusted helper to run the truck on the stands while I got underneath and tried to locate the source of the noise. It could be a rear axle bearing gone south, or like the one in my Burban where the housing was full of pieces of my disintegrating carrier.
Good luck.

[midnightrider78]

Originally Posted by bill3rail

I recently needed to replace my support bearing. Similarly, I had a metal to metal scraping sound. Went underneath and the rubber was worn out. I dropped off the shaft at a drive shaft shop and he replaced all UJ's with new with zerk fittings, hanger bearing and balanced it.

Obviously, I could have installed the UJ's and hanger bearing myself but he had it done in less that two hours with balancing so I was quite happy.

Bill

What did they charge you?
I'm kind of pinching pennies here because I've already spent more on this truck than I should have.

[Steeveedee]

Originally Posted by HO455

I would put it up jack stands and get a trusted helper to run the truck on the stands while I got underneath and tried to locate the source of the noise. It could be a rear axle bearing gone south, or like the one in my Burban where the housing was full of pieces of my disintegrating carrier.
Good luck.

Note- those jack stands should be under the axle housing so that the driveshaft is centered on the bearing. Ask me how I know. I learned that one in about 1975.