The guy was trying to tell you that those mods will help the longevity of the truck and make it tow better. Increased mpg and hp just happen to come along with it.
Go ahead and tow heavy often with a stock LLY. You'll be back on here wanting help with over heating issues and possible hg blown. All the mods do is help it breathe better. An ice engine is nothing but a giant air pump.
I was waiting on it.. somebody getting offended by what I said, even though I did say I don't know much about anything when it comes to tuning diesels. Did I not also clearly ask what would be a good tuner to put on the LLY? Also, if you would have read my 2nd or 3rd post, you'd see the most I'm towing is a 6500# RV, and that's maybe twice every 6 months. 3500-4000lb mostly. If 6500 is considered heavy for these trucks then I might want to stick with a half ton.
Take a chill pill, no hard feelings. I'm just giving my original thought about the subject, and the dude replied respectfully with just straight up what he had to say. Knowing that, the EFI Live might be on my list, while at first, it wasn't. I'm not talking shit to anybody, I'm just stating my original thought, and asking what the thoughts of others are on the subject, which I appreciate them telling me respectfully