Bar rolling up and down during squats

Hello.

I have problems with my squat technique. The bar rolls up and down when I squat. I think it has to do with not displaying the correct thoracic extension, but I don't know how to fix it. I've tried the proud chest clue and the chest up, elbows up clue to no avail. Last Friday I even felt my arms tired just after squatting (like instant soreness) like if I had get some weight in my arms. Perhaps it has something to do with the grip, instead. I don't know. Any help is greatly appreciated.

https://drive.google.com/open?id=10B...VCTx1O5N0hiLqa

Google Drive: Sign-in

"Proud chest" is a stupid cue. Not my idea. Creates the wrong mental image, fucks up a good back angle. You probably have the bar too high on your back. Learn to post videos so we don't have to sign on to Google.

I'm sorry, Rip. I didn't know you have to actually sign on to Google and ask permision to watch it. Here's the link in youtube:

https://youtu.be/tSEySX7OiDY

YouTube

Fat guys always have problems with this, because the roll on your upper back is a squishy place for the bar. This is a good squat otherwise. Try the bar an inch lower.

Thanks, Mark. I appreciate it.