2 days ago I started getting a really wierd noise when I was doing about 70MPH...it was kinda like a rubbing/grinding noise that i could hear at that speed inside the cab. It came and it went and only happened at higher speeds. Yesterday it got a little worse and started happening at about 60MPH here and there. Today it is really bad and happens at anything over 30MPH. It doesn't seem to drag on the truck, but the noise is bad and I can't believe it can go very long like this...I can not only hear it, but feel it too.

It shifts fine, the tranny seems to work perfect. The only other symptom is just after I come to a stop, I feel a bang like it is hitting hard in gear--that never happened before. All gears work fine, including reverse. Tranny and transfer case fluid/filters were changed about 8K ago and both fluids look fine. I'm wondering if this is a torque converter that is going bad?

Its a 93 F150 5.0L 4X4 E40D Auto with Warn manual hubs

 

Check all your driveshaft u-joints, carrier bearing, and slip yoke, if it has one and inspect the shaft for any dents or signs that it might be bent.

 

Also, check your rear pinion yoke. I see a LOT of those come loose, and the bearing just wobbles around, causing a really bad vibration and grinding noise (like marbles in a can). If it just came loose, you may be able to salvage it and just re-tighten the yoke. The PROPER way to fix it is to replace the pinion bearing. This unfortunately requires re-setting up the gears, so try tightening it down first if it's loose.

 

turned out my planet was completely gone, and the chain in my transfer case was bad. I'm getting the whole thing rebuilt...and having the updates to the E40D done.