Fixing my hard to turn door locks on my old truck

My door locks were hard to turn on my old Dodge Ram Cummins diesel. I bought this lubricant to fix some wooden cabinet drawers in my house (worked great) and used it to fix my door locks. It was a little over $15 for a jar and I'd recommend it if you have a hard to turn lock and don't want to break your key. You can purchase it on Amazon: https://amzn.to/3OSEbSO