my car has loud knocking sound, and shifts real hard
think that you need a motor mount and/or a transmission mount~
Doesn't sound like a motor mount, I had to get my motor mount replaced, it just rumbled loud and shook a little but didn't knock. Check the serpentine belt. It may have partially snapped due to wear and cracks in the belt. Have you checked under your hood since the noise started? Is it hard to turn while driving your car? Is the noise constant? If not when does it make the noise?(when turning? braking? accelerating?)
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