Add dry rub ingredients to mixer bowl, mill for 10 sec/speed 8. Pour in to your slow cooker bowl if your bowl is removable and able to go in the fridge. Otherwise just put it in a large bowl.
Remove any butcher string and excess fat from pork roast and pat dry with a paper towel.
Put your pork in the slow cooker bowl and cover liberally with the dry spice rub. Dont throw away any excess just keep it in the bottom of the bowl.
Refrigerate covered over night or atleast 1 hour.
Heat oil up in a large frying pan to medium heat. Take roast out of bowl, leaving excess dry spice rub behind. Brown all sides of the roast.
Return roast to the slow cooker bowl, and cook on low for 8 hours.
Once roast is tender, remove from slow cooker and chop roughly. Return to slow cooker bowl with retained juices and shred with two forks, mix well and serve.