No rust, just a sagging door. Is this easily repaired?

Do you mean its falling on your head or is something really loose in the hinges themselves?

I have seen hinges get a little worn but I was wondering if you meant the struts that hold the whole thing up? Those are available for less than $20 per side, and you can install them yourself without a lot of trouble.

Hope that helps!
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Rob Bareiss, New London CT ::: 87 244DL, 88 245DL, 90 745GL, 84 242DL project, 89 244 parts, 88 244DL to replace the 87

Probably an adjustment.
Usually hinge bolts go into oversize holes. Sometimes there's a sliding plate behind the hole that the bolt actually threads into.

So don't remove all screws - the plate could drop away.

My guess is that with tailgate shut, one half of hinge is vertical, one is horizontal. If door is hanging low, the vertical one needs adjustment. Maybe the screws were left loose by the last person working there, and it worked down.

Best tip on tailgate work I ever saw was to do it with car's rear in your garage. Use a good rope from rafter to hold up the unhinged tailgate.
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Sven: '89 245, IPD sways, electric rad. fan conversion, e-codes, 28+ mpg - auto tranny. 850 mi/week commute. '89 245 #2 (wifemobile). '90 244 (spare, runs).