Spray inside of 4-quart slow cooker with cooking spray. Heat oil in 12-inch nonstick skillet over medium-high heat. Brown roast in oil, about 5 minutes, turning once. Layer carrots, then potatoes in bottom of slow cooker. Pour tomato sauce and gravy over potatoes; sprinkle with soup mix. Place roast on top.
Cover; cook on LOW 9 to 10 hours or until roast is tender.
Remove roast to cutting board. With slotted spoon, remove vegetables and place in serving bowl. Cut roast. Serve meat and vegetables with sauce.