Your lift cables are not all tightened or set to the same length.. you've probably had one of the hooks replaced at some point.
I have a similar situation, I'm in the process of replacing two hooks, the corners are each a different height, with the front left being 0, the front right is 1/2 in higher, back right is 1 1/2 in higher, back left is 1 in higher.
I'm not sure what the allowable difference is, but I think I'm going to replace the other two hooks, since they're bent and try to equalize from there.
1995 Toyota 4Runner SR5 4WD 5 spd
2002 Eagle Summit 12