do you have rear disc brakes?
some blazer with read discs will rub the caliper on the frame when its lowered

 

he'll have rear discs.
Hey Mike, would a 3" drop all around have that issue?

 

yes, my truck does have rear discs. they aren't rubbing anything though.

and it is not the driveshaft either. only does it when i push down on the rear end to simulate suspension flex. gotta be the no name shocks huh?

 

No its not that there no name its that when you lowered them it compressed them so you only have like an inch or so of travel before the shock piston hits the bottom which is making the clunking noise. I had the same problem on my blazer and I had bilsteins. Just make sure to get drop shocks for the front and back and it will help with your ride a ton.

 

he did use drop shocks, also when you use blocks in the rear, like he did, it doesnt change the legnth of the shock. When you use blocks you want a stiffer shock not a shorter one

 

There was defiantly a change. Before I lowered mine my rear leafs and a bend in them, after then didn't. Which would mean that shock position had to have been changed.

The main factor was when i spray painted my rear shocks black and then i took the blocks back out to put the 30's on my blazer there was a noticeable difference where I could see yellow showing.

 

that really doesnt make sense. you arent changing the spring rate or anything all you are doing is moving the axle further from the spring pack. which should have no effect on the springs or shocks

I'm not saying that it didnt happen. it just isnt something that should happen

 

Yeah, you should only need drop shocks on the front.

 

well im about to throw the stock bilsteins back on the rear to see if it makes the noise go away. the front isnt making any noise b/c i can push down the front bumper and it doesnt make the same creeking noise, just the rear.

 

are the ubolts straight up and down?