I have sold my truck long ago to my friend. He absolutely love the hemi power! He said, the engine and transmission are smoothest of all cars and truck I ever owned. Anyways, He texted me about P0440 and P0446 codes. We replaced gas cap.

My plan for the codes is to replace all the hoses to EVAP canister just if we missed cracks in the hose. Its peace of mind. I know EVAP is working as it should. Any other ideas?

Now for PCV valve, I noticed that breather hose is getting covered in oil. It leads to me to think about PCV valve failing slowly. I tried searching about PCV valve replacement and nothing comes up except the the job of valve. I know I'd get the valve from dealer. I have never replaced it since 56k miles and it is at 92k or 93k. I am assuming it is original PCV valve since new. I will check and shake it to see if it rattles or not? Should I replace it for peace of mind?

I will be doing drivetrain fluids pretty soon. I want to make sure I check the C clip however I've never done this part. My bmw and other cars never required taking off the diff cover off to drain. They always have the 2 screws for filling up and draining. How do I check the C clip? (I will search on forums for proper fluids).