I'm new to diesel and can't seem to find why you need a boost gauge. With a stock turbo is does'nt seem like you can have to much boost. Don't linch me but I just can't figure it out.

Well, IMHO it's not really important for a stock setup. I added one because it was a parameter I wanted to be able to monitor as I added components like a programmer and propane. It also lets you know if your turbo is performing properly or if it's starting to have problems.

You only really need one to moniter your turbo if you modify things like the wastegate, or engine tuning. Other than that on a stock truck there really just for fun.

for me, it is helpful to know about mileage when i'm towing. i have a 20 foot cargo trailer that is tall and wide. it's like pulling a parachute.

when i'm into the wind and running 19-20 on the boost, i know that it's futile, and i should back down to 60 mph. any faster and i get crushed on mileage.

when the wind is at my back, and i'm seeing 12-13 on the boost, i'll take her up to 75.

required power goes up exponentially as wind drag increases, so i can net better mileage vs. avg speeds this way.

Boost is very nice to know when pulling a heavier load. You can adjust the throttle based on boost to keep EGTs in check. That's how I do it anyway...