Trim any excess fat from the chuck roast then season it generously with salt and pepper.
Add the oil to a large skillet set over medium-high heat. Once the oil is hot, add the chuck roast and sear it on all sides.
Transfer it into an 8-quart slow cooker then add the onions, garlic, thyme, carrots, celery and potatoes around the roast. Pour in the beef broth and red wine then cover the slow cooker and set it to LOW for 8 hours. (Cooking time may vary based on the thickness of the chuck roast.)
Once the roast is tender, remove it from the slow cooker and shred it then serve it alongside the vegetables.