I was wondering if you guys have any suggestions for what I should check? I noticed recently whenever I'm going up a hill and I give it a little gas, and the trans downshifts into third (700r4), I get a shuddering vibration from the rear. I'm thinking either the rear control arm bushings are getting wallowed out, or maybe the clutches are starting to slip excessively in the posi unit. Any ideas or suggestions anyone else has would be appreciated!