Just noticed it 3 days ago but not on this scale. It happened when I was baking out onto the street, going straight wasn't a problem but when I cut the wheel I felt a drag of sorts, I thought I had maybe gone over the curb a bit and the drag was the tire coming down on the street turned rather than straight. Then yesterday I was bucking when I was backing up straight the entire time. Let me rephrase, when I say it didn't engage I mean it didn't start to move backwards with the foot off the brake, but you could feel it kick in. I have no problem, yet, with the forward gears. I did start to notice a rattle of sorts down by the front driverside tire recently and for a little while now, when the truck is first started and the brake first applied when coming to a stop there is a sort of "clunk" coming from the front end. Also the engine, when idleing, had recently begun to sound as if the fan were hitting something, but in examing it there was no contact with anything, my guess is it maybe just a leak in a vacuum or hose that is causing it to sound off kilter.