Nope. Gots to be tight. If the inner sleeve were to carry all the up-and-down motion, it would wear out in a very short while.

The bushings are meant to flex, in this manner they can move up and down without any kind of sliding friction taking place. They positively locate the upper A-arm and provide a modicum of sound isolation.

Since the rubber itself is doing the flexing, you have to make sure the arm is in a 'neutral' position when you tighten up the nuts. Basically, figure out roughly where the arm is going normally sit, with vehicle weight on the suspension. Tighten the nuts at that point. If you tighten them at one extreme or the other of travel, it'll put undue stress on the bushings and may lead to premature failure.

Hope this makes sense............ed