Define 'loose' - like that side bounces way more? The stock shocks blow (non reservoir) so if it's shot, you might as well upgrade to Progressive 525's or some sport reservoir ones (about $500 for either).
If it's leaning considerably then there's two things to consider. One, it could be a broken spring or mount. Two, it could be worn out.
Check over the mounts and shock holes.
Might be time to get some new shocks.
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