A new noise, I think, from rear driver side. It used to be kind of clacking sound when starting from 0 to about 30 mph, then at a higher speed, the noise can't be heard. Now it is kind of a higher pitch (not screeching) grinding.
I put the wheel up, spin it, and no noise. I took off the drum (without touching the adjuster), spin it, and no noise. After doing this is when clacking sound was gone.
I also went through a flooded road that came up to the floor for about 30 seconds.
It's been also a few days and there is no gas, exhaust or coolant smell.
1996, 4.9 xl, rear drive and about 110K miles.
U joint, bearing, anything in the brake, differential? How to test for this with the wheel bearing the weight?
Thanks in advance.

 

I would take drive shaft off and feel the u joint at the rear end.

 

Thanks for the reply.
Been searching how to and problem solving videos all morning, but nothing conclusive.
It's over 100K miles, so, like the water pump, I am just going to replace some parts. Wheel bearings and u joint.
I am also going to assume this is c clip axle with bearings on the axle housing, not on the axle. All the videos seem to show this.
Also just in case the axle is worn out a little, I am going to use repair bearings.

My question is, anybody doesn't like the repair bearings? I think it is greased and sealed from differential fluid. I am thinking if that seal fails even a bit, the diff fluid will destroy the bearing grease. Would that make any difference? Should be same kind of bearings - I think.

Again, thanks in advance.

 

IMO it sounds like symptoms of a wheel bearing. The order I'd check
-bearing
-u-joints
-differential
Probably not brakes

 

Thank you for the replies.
I am going to change the bearing and u joint anyway, but hand spinning test and u joint inspection turned up nothing.
Since raising the wheel, the noise changed, although still kind of a chattering noise. It also sounds like it's coming from the leaf spring parts. I changed the brackets myself-drilling out existing holes and using 1/2" bolts. That's been more than a few years, though.
I went through a flooded road where the level came up to about the door level for about 30 seconds. The noise started about a week or two after that, but that could be a coincidence. I just don't know.
The truck is 1996 m5od 4.9 2wd xl. I think the rear gear is 8.8.
I'll try spray lubricant over the bolt joints and see what happens.

 

8.8" rear diff is right.
Wheel bearings are lubed by differential fluid, not grease. The seal is on the outside of the bearing.
You don't want to use a repair bearing unless you need one - i.e. damaged axle shaft.
Unless you have trac-lok it's a simple c-clip removal, pull the shafts, pull the bearings (slide hammer or bearing puller), new bearings and seals, put her back together.
Might not be the source of your noise, but after 20 some years a couple new bearings and seals back there sure can't hurt.

 

Put the truck on Jack stands and drive it.

You will hear noise from the spider gears most likely so don't freak out. This happens when one wheel turns and the other one does not.

Just remember not to put it in park until the wheels have stopped.

Having some one with you to hold the accelerator down as you inspect different locations will help also.....

Take a long metal bar and put it to parts of the rear diff as your driving it to help hear were its coming from it needed...Just put your ear to the bar.

 

Thank you all for the replies.

What's wrong with using the repair bearings? Since the inside axle has to be removed to find out, I thought it was just as well to buy the repair bearings, although the repair bearing use grease, instead of depending on the differential fluid?
If it changes the positioning of the axle or something in relation to the gears in the differential, I will get the regular bearings/seal as well.

 

I don't know what repair bearings are, but why not put what's supposed to be in there in there? The rear bearings as stated above are lubed by differential oil, so unless the repair bearings have a seal on the inside and out side of them I don't know why they would use grease? Am I reading this correctly?

 

Sorry, missed this post. Do you have to drive this truck every day? In my book, 100k miles is not high and the axle shouldn't be worn to the point that you can't use normal bearings unless the old ones have been running dry. If you don't need the truck and can have it down a few days, take it apart and inspect your problem, then buy the needed parts. Or possibly (depending where you buy the parts) Buy everything you may need and return what you don't use. And, as a personal preference I highly recommend Timken bearings.