Rythmic thumping noise after installing new strut. please help

2008 GMC sierra. Just installed new quick strut on driver side, and now I am hearing and feeling a rythmic thumping coming from that side that I can feel in the steering wheel. it increases and decreases with the RPM of the wheel. it seems to get louder when slowing down and braking. turning has no effect on it. New tires were put on before all of this. the lug nuts are torqued to spec along with all the fasteners on the strut.

Any idea what could be causing this?

Maybe the new strut is bad.

Have someone drive along side you in another vehicle to see if the tire is bouncing.

Tester

Jack it up, pull the wheel off and take a good look at it. Look for areas where the paint was rubbed off by the tire. Check the tire for damage, rub marks, something you ran over. You may have installed it wrong. The strut may be built wrong. You won’t know unless you check.