Hi my truck started to knock really hard when I push the clutch or when I accelerate, if I stay at the same speed the noise comes out but starts again when accelerating.

Also, I had problem engaging gears so I'm asking myself if it's the clutch that is worn out. I would like to know if there's a way to know if the problem really comes from the clutch before I take my transmission off...

Thanks

 

Cracked flywheel maybe? Or pressure plate.