Clunking Sound at Low Speeds

[onecrazyfoo4u]

My 05 1500 5.3l auto has some obnoxious clunking sounds at low speeds.  It doesn't seem to happen when driving straight and level, but only when turning at low speeds (like in a parking lot).  At least that's the only time I can hear it, when going to park or something.  And it seems to go away when I tap the brakes.  So only clunks at lower speeds while turning and not applying the brakes.  It appears to be coming from the front end somewhere. 

 

What do you guys think it would be?  I've gone over all suspension and brake components to make sure nothing was loose or broken.  Where should I look?  The grease zerks haven't been serviced since I bought the truck 2 years ago.  Could that be a problem?  What are the locations of all the zerks? 

[Mike GMC]

Check the CV joints on the front axles.  If the rubber boot is ripped, it's likely toast.

[onecrazyfoo4u]

Well that doesn't look like a fun job.  I just replaced the axle shaft seals.  Hopefully I didn't break anything on the CV joint when I undid the 5 or 6 bolts holding onto the axle shaft.  I did notice a tiny little tear in one, but no grease coming out of it.  How do you check if the CV joints are good or bad?

[onecrazyfoo4u]

Also, there is a huge price difference between AC Delco and other brand names ($300 each vs $50 each).  Do people use the other brands with success?  Or is this one of those things where you should stick with the AC Delco?

[Mike GMC]

Generally, popping sound you described is the tell tail sign.  A ripped boot it just confirmation.  No clue on best brand.