Possibly the most common mistake I see when deadlifts get heavy is the bar drifting away from the body.
Many lifters assume that a deadlift is just picking the bar straight up, but this isn't effective. As you pile on the plates, you need to think about actively engaging the lats and pulling the bar back into your body so that your weight shifts backward slightly.
Keeping the bar in tight helps ensure every pull is smooth and efficient.
Get stronger on pull-ups and you'll get better at just about everything. Here's how to do it, whether you can crank out a dozen or you're working on your first strict rep.
When you have knee or shoulder issues, this is a good alternative to a standard squat. This is the touch-and-go version with chains for overload at the top.