I just came back from the big Cummins dealer in town after having the Valves reset,timing slight change, total flush and refill of cooling system with ext-life again, Differential drained and filled with my Amsoil Gear oil(I supplied) and they did a brake adjust as it seems the adjustment was quite a bit off.
I was also given 2 galls of coolant as spare. Total $900.00 cdn (or $49.99 us) he he.
Not too bad I think!!
Sounds like my trip but no coolant flush.