Engine
 

Hello my name is james. I recently bought a 2001 monte carlo ss 3.8 and it ran fine the first three days i had it. Out of nowhere i had an engine knock the next day so i swapped it out with another engine and it ran fine then once again i got another knock three days later. Oil was full both times and i dont know what else can be causing this issue.

Been in that predicament myself a few times.
When you ask about something knocking; it could be for many reasons.
I'll guarantee you one thing.
That ain't opportunity knockin'!

Engine
 

Its crazy because only 118,000 miles were on the engine. I took the first one out and took off the manifold and found metal shavings and the rod was spinning freely

Hey James.
Please give us more info.
Did you replace just the block?
Did you reuse the old heads?
What other accessories were reused?

Agree with plumbob, need more info

I replaced the whole engine twice both times had different parts

I put 309 miles on the engine i just put in soo far so good but now I'm having another issue. My car makes a clunking noise and has a harsh shift when goimg in reverse. All other gears are fine and it shifts smooth when driving except for one time it started to shift hard through all gears and i restarted the car and it ran fine after so i was thinking maybe its the psc (pressure control solenoid)?

Common symptom of the solenoid starting to go, they have replacements you can buy ZZP Platforms but not sure how much it costs to have them installed, they have videos on you tube of how to do it though as it sounds as if you are mechanically inclined

Also I'm curious if anyone has had an issue with the turn signals, when i turn the key to on my turn signals work fine but when i put it into any gear they flash radically, if i put the left one on they both light up at the Same time but one side is a faint light, the wierd part is when i hit the fog light button the arrows freeze on the dash and dont work and my hazards work fine

Sounds like you've had bad luck with engines, you need a new solenoid or two in the transmission, and/or you have a cracked flexplate, and you need a new multifunction switch. Wouldn't hurt to check your bulbs though.