Mix Beer, Cream Of Mushroom Soup, Onion Soup Mix, Onion, And Garlic Together In A Slow Cooker. Season Beef Chuck Roast With Salt And Pepper, And Place In The Slow Cooker. Arrange The Carrots And Potatoes Around The Meat. Cook On Low For 6 Hours, Then Add The Celery. Continue Cooking Until The Roast Falls Apart Easily And The Potatoes Are Softened, About 2 Hours More. Serve The Meat And Vegetables With The Remaining Gravy On Top.