The HD strut mounts are great. I had the strut nut come loose on mine (on top of the strut) and it made a sound similar to yours at low speeds, especially over bumps. As Sleeper said, the sway bar end links can make the same noise too. They are both difficult to properly tighten.

 

Blue Loctite is your friend!

 

what are you supposed to use the blue loctite on the panhard rod???

 

On all of the bolts/nuts and if you have an adjustable one on the jam nuts

 

i was praying it was just the swaybar endlinks, but i went under there and tightened absolutely everything. the strut nut on top (as red06 noted) was the only thing that would budge, but this noise seems to have gotten worse over the last week, and i /needwant to avoid the $300 steeda hd mounts if possible

 

Did you put the rubber isolators on the bottom winding of the replacement springs?

 

I have a set of used J&M adjustable camber plates I'll sell you. They are in very good shape, approx 10K on them, never any hint of the dreaded 'klunk'. If your issue is the strut mount, these will solve it and give you adjustability as a bonus. $150 + shipping. Here is a link to them: J&M Camber Plates