Rear axle bearings

[steppside69]

I have a question about the rear axle bearing, I was changing the rear brakes on my truck and noticed what appears to me to be ALOT of play both thrust (About 1/4-3/8") And up and down (About 1/16 + or -") I dont know if that is acceptable or I have a problem?

The truck is a 2006 silverado z71 ext. cab 5.3l
It has 80k miles and has a intermediate noise from 1st to 2nd. Sometimes it will make a clunking sound but will not do it all the time. I also noticed a slight vibration when coasting to a stop light. Thought that it maybe in the tranny so I put the truck in neutral while coasting and the vibration was still there. I hope that there is nothing wrong but my gut is saying something else, Thanks for the info/guidence
Eric

[usmcchevy]

The thrust doesn't sound too far off of normal (c clip type rear) and usually the seal will start leaking pretty quick if the outer bearing is allowing too much up/ down movement.
Vibration I would disconnect the drive shaft and spin the rear by hand and check the u joints.

[steppside69]

I checked to u-joints and had to hold the drive shaft while a friend turned the tire. There is some play so i will change the u-joints this weekend.

Will keep you guys informed of the progress,
Thanks again for the info, Eric