This thing sucks at stopping, pulling hills, among other things I feel may be improved by going back to stock tires. Think I'll make that switch for the next trip to see how it goes. I will miss hogging at 70mph/2100rpm, but I think it's a loss in all other areas. Wish this were a 3.55 truck.
Seems to be gradually revving slower and slower above 2200 or so. Fuel pressure is solid, hoping maybe just something stupid like clogged air filter. Will try that. EGTs seem to climb with higher rpms? 4th to 5th seems to lower EGTs... seems counter-intuitive.
Has a weird pulsating leaking sound that almost sounds like a boost leak? Hard to track down and does not do it unless letting off from a heavy load. Burnt fuel smell is accompanied with this symptom, but no large wet spots found anywhere. Series of small dark drip spots under truck, hard to identify whether fuel or oil... suspecting fuel. Will tighten all hose clamp connections I guess.
If newer Cummins trucks weren't expensive to buy, maintain, and put fuel in... I might consider upgrading. I need to fix all these little things so I can stand to sit in this thing for 5 hours.