I'm planning to replace the rail pressure relief valve on my 2004.5 Cummins and had some tool and procedure questions. I know the banjo bolt is 3/4" and the valve itself takes 15/16" or 24mm deepwell socket. There is a video about replacing the relief valve, but it doesn't say anything about loosening the return line further downstream.


1) What brand 15/16" or 24mm deep well sockets are deep enough to fully engage? I bought a 15/16" deep well from Harbor Freight, but there is a lip inside that bottoms out on the top of the valve preventing any engagement.

2) What size is the bolt down stream from the valve? It bolts the return line to the fuel filter housing and looks like it may need to be removed to be able to move the solid line and fitting aside for room to remove/replace the relief valve.

3) Am I missing any steps or anything to look out for?

Thanks.