All of 'em. They weren't just sloppy loose, but they were loose enough for movement... Yeah, they're tight now. Any tighter and I'd be worried about damaging something.
I would be suspect of insufficient leverage/torque error too.. but maybe chances are better than we think. there's a lot of torsional movement, twisting and vibration on those things which makes them act just like lugnuts after a while. 2 loose lugnuts can cause all sorts of issues. Don't ask me how I know that and I won't need to post pictures.
What I'm afraid of is that those 1" lowering blocks may have compressed a bit. I'd be a lot more comfortable thinking I just failed to tighten them, but I don't think so.
I would replace them or check them to make sure the alignment tabs haven't broken off. I had a block (stock factory placement) come out on my Bronco because the u-bolts loosened and the alignment pin was sheared. Snapped all but 1 of the u-bolts and left my rear-end floating free under the truck. That was not fun. The guy at the ford stealership told me that is a common failing on the blocks if the bolts come loose.
I've had many lowered cars and trucks and the only issue I've ever seen with some of the thinner cast spacers is cracking. Even if you bottomed out the suspension with a trunkload of sandbags.. I highly doubt that you could ever "squish" that aluminum. Torque variation issues caused by expansion/contraction would be more likely than squished spacers. PS. Hi-temp loctite will easily take care of lost torque settings and I use it on EVERY load critical suspension component that I may have apart on my cars during mod's or service. I used to put anti-sieze on just about everything underneath a car thinking that I would need to eventually service it anyways.. but after a few of my own.. and watching others "boo boo's".. I'd rather have to get the torch out to remove a stubborn nut/bolt versus having it come loose during racing or high speed cruising.
I can't agree with that more. I went from doing mechanic work on industrial machines to cars, and had to re-teach myself that it was ok to put loc-tite on things. I still find myself forgetting the loc-tite and having to retighten bolts that I shouldn't.
I had a set of aluminum lowering blocks that had open castings in the middle of the block that allowed the rounded spring pads on the Maverick rear to sink into them, throwing pinion angle off. That could also allow the bolts to get loose. I have since made some out of steel and I tossed the factory lock nuts in favor of tall standard nuts with a jam nut on each bolt end.