I have a 2000 Buick Century Custom with cloth seats. Everytime we exit the car we get a shock. I put a ground strap on, But no luck!
You could wear a wetsuit!
The problem isn’t the car getting charged up - it’s you getting charged up! The ground strap on the car only makes the car give you a potentially bigger shock! What you need to do is get a car seat cover that is made of some kind if insulating material like rubber or one of those ones made from wooden beads. You can try changing your wardrobe too - those polyester suits don’t help!
As a last resort - you can go to a Radio Shack or find an online electronics supplier (digi-key.com for example) and purchase a “grounding wrist strap”. This is a device used by electronic technicians to stop static electricity. It is a conductive wrist strap you wear that has a wire coming from it that attaches to ground. You can attach the wire to a metal part of your car and you donb’t need to wear the wrist strap - just pick it up and hold it for a few seconds before you touch the door handle.