Drivetrain noise

[BNesseler_1970]

Have a slight clunking noise when I kick it down to pass. Have replaced all u-joints and still makes the noise. Not all the time...but every once in a while. Truck only has 54000 miles on it and I can't figure out what the noise is. Any ideas ? Truck is a V8 AWD.

 

[jgilbs]

maybe its your transfer case engaging? do you have a lot of pickup when you accelerate(ie would the tires be spinning it it was 2wd?)