I believe the yellow Norco pills are the strongest. They are 1000mg if I'm not mistaken. My ex used to take them for back pain and they do work pretty well in my opinion. I have taken them before as well. I have never seen them in any other color, but I do believe those are not as strong as the yellow ones.
No, they're all the same, 10mg hydrocodone and 325mg acetaminophen. I have been taking them for 15 years and cannot tell the difference. Sometimes the yellow ones that are made by Watson or the ones that have the V on them will not affect me the same all the time, seems like they're fresher sometimes. I don't know about the blue ones, they're the name brand, says Norco on them. I heard those ones are stronger but my insurance wont let me have them or the pharmacies never have them here in B'ham Al.