Loud Grinding Noise at start up

Terry Ansley Jr. · February 23, 2017

I recently purchased a 2006 Chevy Silverado 4.8L, 4x2, 5 speed manual in December. I have had no problems with it until yesterday. When I left for work was driving in my neighborhood when there was this knocking noise like something was rolling around in the bed. It happened twice and nothing for the rest of the trip. When I got off of work, as soon as I started to drive there was this loud knocking noise and I could feel it under on the floor and steering wheel. I pulled back into the parking lot and everything sounded normal, engine was running smooth, I was able to shift easily. After a couple minutes I decided to try again. It made the same knocking noise but not as pronounced then went away like nothing ever happened. I was wondering if the parking brake could have got stuck then loosened up. Any ideas? I am at a loss.

Dnt · February 23, 2017

Motor mount is sheared have it replaced as soon as possible before the engine turns upside down in the engine bay

Terry Ansley Jr. · February 23, 2017

If it's the motor mount wouldn't the knocking happen all the time?

I started it up this morning, but this time I noticed that the truck did not want to back down the driveway in neutral. I even shifted in reverse and there was resistance.

I took it down the street slowly and a couple times there was a loud knock that even my neighbor heard. Also the steering felt tight. But after a couple minutes everything was normal.

I'm going to take it in since it's still under warranty, but I want to try and pin point the problem, so they know what to look for.