Thank you Cody. Your explanation of the huge range in A/F ratios for a diesel was a real eye-opener. I had no idea there was such variance. I DID think there was a difference in burn rate though.
And, I knew lean gassers burned hot, which is what is damaging. I did not know that rich diesels burn hot. Yes, I can see that lugging causes a rich mixture, given what you describe. Why the heck does a rich diesel mixture run hot when a rich gas mixture doesn't?
And, isn't "lugging" a "heavy" load for both? Couldn't the A/F ratio for a diesel be adjusted for this condition to keep from being too rich?
I totally resonate with this statement: "Only controlled experimentation will tell.
In my position, driveability reins over economy....mostly because people in my neck of the woods USE their trucks." I hope you did not think I was suggesting some kind of tune that made the truck marginal to drive. I certainly do not have that kind of tune in my truck and would not want one.
As I've said in many other posts, I seem to pass all the other RV's and trucks whenever I take my truck and trailer up over the high mountain passes in Colorado.
I still have trouble equating "Vigo" with you!
- Jack