If the dead body is completely dead as in brain dead, heart dead etc then the dead body will not be able to feel any pain.
To be able to feel any pain the body has to have at least an alive brain where the pain receptors are working because you need your pain receptors in the brain working and alive to feel pain.
You feel pain because the nerves then send signals to the brain which then processes the pain.
So if you're completely dead then you cannot and will not feel any pain.
If the dead body is not really completely dead and only partially dead or just happens to be in just a coma then the body could feel pain.
But when the body is completely dead then no pain will be felt by the body.