In a large skillet, heat 2 tablespoons of the olive oil. Season the beef with salt and pepper and cook over moderately high heat until browned all over. Transfer the beef to the slow cooker, cover and turn it on to high. Add the sausages to the slow cooker.
Add the remaining tablespoon of olive oil to the skillet and add the pancetta. Cook until brown and the fat has mostly rendered out, about 5-7 minutes. Add the onion and garlic. Cook until soft, about 5 minutes
Add the red wine and stir to release any browned bits on the bottom of the skillet. . Bring the wine to a boil and cook until reduced by half, about 4 minutes.
Transfer the mixture to the slow cooker and add the thyme, rosemary and water.
Add the tomatoes and their juices and the tomato puree to the slow cooker.
Cover the slow cooker and cook on high for 4 hours or low on 8 hours.
Transfer the beef to a bowl and remove it from the bone. Shred with 2 forks or with a knife. Return the meat to the cooker (lid off) and simmer the sauce on high for 15 to 30 minutes longer.
Discard the thyme and rosemary sprigs and season the sauce with salt and pepper.
Serve over pasta, mashed potatoes, or polenta with grated pecorino Romano cheese.