[77newell]

My 77 coach originally had the 555 with 230hp which for a 29000 pound coach is pretty meager. It was replaced with a 350 hp 6V92T and has rather spritely performance. Since I don't know all the particulars of the change I can't say why it was done.

If I was in your situation, as I understand it, I would have an engine oil, engine coolant and transmission oil analysis done before I did anything drastic. If you find the engine is doing at least OK then you buy time to figure out what to do when you finally decide to do the change. Figuring it all out can be fun and finding parts in very good condition at a reasonable cost probably will take awhile.

Unless you plan to go with with a side radiator I doubt an inline 6 will fit.

I love our coach and the attention it gets when we are parked.