Trim fat from pork roast, if necessary. Place roast in 4- to 6-quart slow cooker. Use wire whisk to stir together cranberry sauce and sugar in medium bowl.
Stir in juice, mustard, cloves and pepper until well combined. Pour cranberry mixture over roast in slow cooker.
Cover slow cooker and cook on low for 6 to 8 hours or until pork roast is tender. Season roast to taste with salt; serve juices with roast.