My leaf springs just started squeaking???

I have noticed just in the past week or so that my leaf pack is making a squeaking sound... I can only hear it at slow speeds, mostly when I open up my door to look behind me to back into a spot.

Just curious... They haven't been doing this, even after adding the AAL it didn't squeak? Any reasons why this would start all of the sudden?

I was wondering if maybe it could be from when I got under there and re-tightened the u-bolts? I didn't torque them so when I was doing my brakes a few weeks ago I went ahead and cranked the u-bolts down to make sure nothing had come loose since installing the AAL. Could over torqueing the u-bolts be the cause?

If not how do I make it stop??? I tried wd-40 but, that didn't work.

Thanks in advance,

Jason