I presume you have lubricated upper and lower bushings of each door hinge and swung door over it's full range a half dozen or so times to work the lubricant in before reaching this point.
I frankly would suspect door hinge pins/bushings before check strap as source of problem. Easiest next step would be to disconnect check strap at door jamb and see if this removes the gritty feel when you swing door. If not, then it confirms hinges are problem. If it does, then check strap was the problem and you can proceed to remove door panel.
You used to be able to get hinge pin/bushing replacement kits for some car hinges (usually to eliminate door sag). Don't know if you can remove pins and/or get replacements for Contour or whether replacement of whole hinge the only option.
Good luck.
