The other day I was driving my 2009 Jeep Grand Cherokee Laredo on the highway and some jackwagon cut me off and slammed on the brakes. I hit the brakes and swerved to avoid hitting him, and a few miles down the road noticed an awful squealing (grinding?) noise. After slowing down it started to go away, and then came back so I pulled over, took a look at the engine, belts, etc. and didn't notice anything immediately wrong, so drove some more and it came back. Usually sounds and drives fine at low speeds, but then has difficulty getting up to speed and the noise comes back around 45 mph. It's slightly noticeable when turning at low speeds. With my limited knowledge, I'm thinking it is either a bearing or u-joint, but definitely would like some input from the forum so have at it!

Thanks

 

I think you are on the right track. A marginal bearing got hit with a sudden swerve (lateral force) and hard braking at the same time, and it was enough to send it over the edge.

I would bet on a bearing rather than a U-joint.

Get it up on jack stands and slowly rotate the tires. Feel for it as much as listen for it.