I have a 2016 ram 3500 with 50,000 miles that I use to haul a truck camper and pull a heavy boat. I drive up and down the same grade fairly often. Sometimes the engine brake works, other times it doesn’t. This issue has been going on for about a year and it never throws any codes or has any other symptoms. The truck is all stock with a 68RFE transmission. I pulled the exhaust gas pressure sensor the other day and it looked clean and the tube looked clear. Without any engine codes I’m not sure what direction to go, has anybody seen anything like this before?