How long do I cook a 10 lb chuck roast in my crock pot?
Always 145 for internal tempature. Set on low or warm, should take 10 hours. Similar to smoking, low and slow makes the best meat.
Not sure about comments on cooking too 160 and over, sounds like they are making leather, not meat. If you go this high MAKE sure you have very fatty meat (like brisket).
Be sure to braise roast before slow cooking.
As comments mentioned many slow cookers are way to high, so results may vary. I found an old model that will hold 145-150 on low setting.