My father and I both drive GMC 2500’s. He is keeping his 2001 2500, as his ranch truck. He needs a 1500 for a day to day truck needing much better MPG. We have found a 2018 Chevy 1500 double cab with the 4.3 V6 ecotech3 (rated at 18-2mph) that we are considering.
After he adds a headache rack, tool box, and grill guard, will the V6 still get the better MPG or at that point should we consider the 5.3 V8 (rated at 16-22mpg) to handle the weight and actually get better MPG (combined town and highway)?

 

Theoretically it will, even adding the weight, but I don't think it'd be worth it, you'd prolly get real close to the same numbers out of the 5.3, but I could be wrong, I never knew the older 4.3's to get that much better mpg's. It being a 18, it might be better, but all that said, I'm not incredibly impressed with the mpg's on my 14 5.3 I just got, really not much better than my 00. I'm talking literally maybe 1-2mpg, which seems to be about the same difference they say you'll get between the 4.3 and 5.3.
I'd prolly play it safe and go with the 5.3 just to have the power, if he doesn't hammer on it, it should get ok mileage.

I just put the first tank of e85 in it yesterday, consensus seems to be that I'll lose some mpg, but it'll feel stronger, I guess we'll see. I did a ~300 mile trip yesterday and got 17, but my 00 got 17 going about the same mileage. I really did expect more beings the 00 has the 4 speed and 3.73 gears, and the 14 has the 6 speed and 3.09 and the whole v-4 deal.

 

In my experience a 2018 5.3 will get the same or better economy as a 2001 4.3

 

Thank you guys. In this case it is
2018 vs 2018. Do y’all still feel the same regarding the 4.3 versus the 5.3 in the same year?

 

if you're looking for fuel economy, then get an SUV not a truck. Does he really need another pickup? Of course the 4.3 will get better economy. that's been tested.

fueleconomy.gov

 

It would make sense that a newer truck would get a better mileage, my 2017 4.3 4x4 DC Silverado gets 20-21.

 

Thanks all for sharing.

 

My milage last night