Rear end vibration

[Brian1973]

I'm thinking rear axle bearings at 175k miles never changed. Feels in the driveline and seems more than just a wheel weight being off. Vibration seems more noticeable during highway speeds and severity varies with acceleration and deceleration. I'm thinking there are bearings at the wheels and at the differential? As well as the seal being replaced at the wheels. Is there somewhere on here I can find a schematic of this? Ideas on all of this?

 

[RonD]

It is a tire or wheel problem 99% of the time
The other 1% is drive shaft

Axle bearings tend to last the life if the vehicle, they can fail just like pinion bearing or other differential parts, but these failures usually have a louder "hum" associated with them, maybe some vibration but that would come later, "hum" would be noticed first.


Rotate tires/wheels back to front, that's the simplest free test

I had a tire that had belts separate inside, weird vibration at certain speeds, it seemed balanced with no pressure on the tire, because it was balanced.
But as soon as you put weight on it and went out for a drive it would vibrate

 

[Brian1973]

It definitely hums as I go hwy speeds. When I spin both axles, without wheels on them (as I'm doing brakes), I can feel vibration. Shouldn't it be smooth?

 

[Brian1973]

and U-joints replaced last winter thinking that might be the issue. Doesn't get a lot of hwy miles on it until lately and it reminded me that it was still unresolved :-(

 

[Brian1973]

just FYI if someone ever queries this thread... couple months ago took truck to the shop and they confirmed it was the pinion bearing that had gone bad. $800 later, hum is gone... Seemed better right after fix but recently seems to hum a little at just slight acceleration... but no vibration like it was. Shop seemed to think the slight hum is just the gears possibly a little beat up from the tore up pinion bearing 95% better than it was so not replacing gears in it unless it absolutely needs it!