Riding rough and vibrating at highway speeds after rack and pinion repair

Hi there. I have a Lexus RX 350 and about a month and a half ago I got the rack and pinion replaced. Pretty shortly after, as I was driving highways speeds somewhere in the 60-70 range, it started to feel a little rough, as if I was driving over rough pavement, but it was brand new blacktop. I put the brakes on and the vehicle started to vibrate, not the steering wheel though. After I braked, the rough sound and vibration didn’t come back until a week or two ago, it’s been happening intermittently and very seldom, maybe has happened a total of 5 or 6 times, but I’m concerned because it never did this before the rack and pinion. I got it all done on a Saturday, alignment was involved too, so I wonder if maybe someone hurried themselves and didn’t do something to protocol. Any ideas on this? Any questions you have that would give more information I would gladly provide. Thanks in advance.

Is there some reason you have not talked to the place that did the work?

Recheck the lug nuts.