Knocking noises while turning the steering

This is actually a follow up to my last question which was about the metal scraping cyclic noise
As is said in that question the Dodge dealer I'm my country gave me a bill of above $4700 to eliminate all the noise by changing all the front suspension arms, front shocks and all the brake rotors.
I took it to a local mechanic I knew and he changed all the front bushings and knocking noises where gone, I have the car for wheel alignment and then rust protection and some of those noises started coming back, but the would come occasionally, so the mechanic didn't hear them the first 2 times I took the car back to him.
It's okay after a long drive the scraping noise went away, but I got all the front bushings changed and the ball knuckles still when I back up the car in my garage which is higher than ground level and is a slope I can hear the knocking noises coming back again which went away in the beginning when I got the work done on the front suspension. Also, occasionally there is a thump low bass noise when I turn the steering wheel parking or low speed cruising and it doesn't come when I take it to the mechanic, but it comes occasionally, but too often now, I would imagine having the whole front bushings, ball knuckles and other stuff changed these noise won't be back for another 2 years since I drive this car very less and the mechanic is too far for me to hear the noise and just drive off to to him it'll take the whole day.

What could be those knocking noises and that low bass thump durm lighly banged noise while I turn the steering?
Also when I turn it full at the end of turning the steering I feel a resistance

I'll really appreciate your help on this.

Thank you
Omran