My doors on my 1991 F250 are a pain to close. They have to be slammed repeatedly to make the doors latch.
I tried to clean the latches without removing them by spraying brake clean into them (to remove crud) followed by WD-40 (to act as a solvent and lightly oil) followed by white spray lithium grease.
Can't say that it helped any.
Are the latches just worn out? Or is there something inside that can be replaced on the latches?

Thanks for any replies...

 

I would bet it's not your latches.. I would put my money on the door hinge pins being loose... and the doors sagging...

 

i have the same problem. i don't think its my hinges. theres no wobble in my door if i try and pick up on it when its open. if it is the hinges, you can buy new pins and bushings from Truck Parts and Truck Accessories for Chevy, GMC, Ford and Dodge Trucks from LMCTruck.com for $7.50 a hinge. the old pins have to be drilled out. it sure beats $50 each for the hinges.