Driveshaft help!

So my truck started making some pretty strange noises. When I accelerate at about 45-50mph it sounds like a coaches whistle, seriously sounds just like it.

When I decelerate it makes like a snapping noise and I start to get some vibrations. The motor seems to preform sluggish in the 30mph range but then if I rev above 2k it seems like boosters kick in. The noises sound like their coming from the back of the truck.

I crawled underneath and checked the u joints but I wasn't really sure what I was looking for. I also looked at the carrier bearing where the two piece driveshaft meets up and I could wiggle the driveshaft around inside it. I t looks like theres a huge bushing in there so I'm not sure if that's normal. Any advice...Thanks

 

When was the last time you lubricated your driveshaft/ujoints?

I would start there....lubricate, lubricate, lubricate.

I lubricate mine at 30K miles. After greasing, I always get strange noises until a couple days later when the grease has worked its way around the entire bearing.

Carrier bearing is supposed to 'wiggle' a bit. Rubber bushing.... not supposed to be rigid.