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The reality is these motors are designed for a 150K life span, some don't make it that far, others go farther. How it was taken care of has some effect, but that doesn't change the fact the motor was designed to die at 150K. Back in the old days, that 150K was probably acceptable because most vehicles didn't make it that far, but by today's standards, 150K should be "just broken in" not "just about broke."
I had a 2002 Ram 1500 with this engine. It ran fine but was a slug. Gutless. The mileage was not great, maybe 17 freeway on flat ground. I ran it up to 163,000 miles and sold it when I bought a 2006 Ram 1500 4wd 5.7. The 2006 got better mileage and made more power!
The 2002 though...Spark plug changes were easy...Straight down through the intake! They had an interesting oil filter drainage trough too....I wish the 383-440 engines had something similar!
