New style? The oil pressure sensor on a Cummins ISC is a simple electrinic switch - it reports pressure as OK or Not OK. Not a value.Its a side rad model the sensor is above the starter easily accessible I would have done it myself but they said it had to be programmed into computer cause it was new style so 1/2 hour to repl sensor 5 1/2 to program Oh well only $1056
The rig the OP has is a diesel, and he/she obviously went to a Cummins service shop. The one we go to for routine things is a Freightliner Oasis shop with extra training in motorhomes. They always have a few in the place plus lots and lots of trucks. One of the advantages of a DP is that there are an awful lot of Freightliner and Cummins shops who are quite comfortable working on them and have the facilities to accommodate large heavy vehicles.Typical for auto repair work to have a set number of hours it will typically take and they charge this, which is a nation-wide collective set of info. If they do it faster or slower then that is on them.
So, an oil change that should take 20 mins they will charge you for 20 mins plus parts. If it takes them an hour then you still pay the 20 min rate. Fast mechanics can make more money than slow ones for this reason.
Goofey RVs might not be common enough to be put into the book of repairs though. 6 hours is not a huge charge for doing anything under the bonnet though. Most auto repair places would refuse an RV just because they will waste a lot of time figuring out how to work on it or get to it , where they are used to cars n trucks and know the end before they even pop the hood bc they do it so often.
It's not at all obvious to me that the OP went to a "Cummins service shop". Unless perhaps you define that as any shop that will work on a Cummins engine. Larger RV dealers may do chassis work, but that doesn't make them Cummins experts or mean they use the same flat rate manual that a Cummins service center or a Freightliner Oasis dealer might use. Especially on a motorhome, which is more often serviced on a time & materials basis.The rig the OP has is a diesel, and he/she obviously went to a Cummins service shop.
Hmm, well, to ponder this, I guess I assumed it was obvious that auto repair and truck repair and anything in between would have a similar flat rate hourly billing system. Im not sure if this answers your question or not.So why did you spend time talking about automobile repair places not taking RVs? It doesn’t apply to the situation at all.