Strange Chattering/ticking Noise While Taking Off

[sledr]

I have an '04 Silverado Z71 SBEC w/5.3 with 150000kms on it. Yesterday I noticed while accelerating away from a red light there was a chattering or ticking noise coming from the truck. If I ease into the gas there no noise. Today I backed out of the driveway and heard a snap coming from the rear (left) when I shifted into drive. The ticking noise seems a little louder today. Also if I accelerate from 40-50km/h I can hear a faint ticking. The trans fluid is fine also. I did some testing in the driveway going back and forth slowly. Each time I stop completely and shift into drive there is the snapping noise coming from the rear. When doing this it distinctly sounds like it is coming from the left rear. Any ideas???

[MYZ-71]

I have an '04 Silverado Z71 SBEC w/5.3 with 150000kms on it. Yesterday I noticed while accelerating away from a red light there was a chattering or ticking noise coming from the truck. If I ease into the gas there no noise. Today I backed out of the driveway and heard a snap coming from the rear (left) when I shifted into drive. The ticking noise seems a little louder today. Also if I accelerate from 40-50km/h I can hear a faint ticking. The trans fluid is fine also. I did some testing in the driveway going back and forth slowly. Each time I stop completely and shift into drive there is the snapping noise coming from the rear. When doing this it distinctly sounds like it is coming from the left rear. Any ideas???

[MYZ-71]

Sounds like a u-joint to me, most likely the rear joint at the rear diff, may feel tight when checked but look for signs of rust coming out of caps.