I recently purchased a 1994(ish) Polaris Trail Boss 350L and I’ve found that using the gear shifter is quite difficult. It makes a loud grinding sound and often doesn’t actually change to the gear I want (reverse being most apparent). Any tips or repairs would be appreciated!

I recently purchased a 1994(ish) Polaris Trail Boss 350L and I’ve found that using the gear shifter is quite difficult. It makes a loud grinding sound and often doesn’t actually change to the gear I want (reverse being most apparent). Any tips or repairs would be appreciated!