Tailgate stiff to open

Hi all.

My tailgate is really stiff to open, I though it was the gas damper but removed it today discovered its the hinges. They look in good condition but I have to push quite hard to open and close the door.

Anyone come across this?

If wd40 doesnt help they may be bent i have seen this when heavy tyres are hung on them

The lower hinge on mine seized, needs careful repeated application of oil.

The bonnet hinges seize up too, and the entire car has to come apart to oil them as they are under the black plastic below the screen

Thanks Guys, I'll go and lube em up for starters.