Towing fuel mileage

[Rbaker]

I just bought a 2023 Silverado 5.3 10 speed auto 4x4 and really like it but I just towed my small pontoon boat for the first time and am very disappointed.
I have been towing this boat with a Colorado previously with no problem the boat is small.
My mileage went from 21 to 7.5 MPG and the truck is in no strain , is there something I am missing because this is terrible.

 

[zora]

I just bought a 2023 Silverado 5.3 10 speed auto 4x4 and really like it but I just towed my small pontoon boat for the first time and am very disappointed.
I have been towing this boat with a Colorado previously with no problem the boat is small.
My mileage went from 21 to 7.5 MPG and the truck is in no strain , is there something I am missing because this is terrible.

Are you relying on the computer or actually computing based on miles driven and number of gallons to refill?

 

[Rbaker]

Are you relying on the computer or actually computing based on miles driven and number of gallons to refill?

I haven’t done actual miles but I have compared the exact trip with and without the boat I usually make the trip on around 1/2 tank of gas and with the boat I actually filled up when I left and had to refill about 70 miles before getting to exact same place going the exact same route.

 

[zora]

I haven’t done actual miles but I have compared the exact trip with and without the boat I usually make the trip on around 1/2 tank of gas and with the boat I actually filled up when I left and had to refill about 70 miles before getting to exact same place going the exact same route.

So you don't know if it's actually a mpg issue or the pump shutting off early or the gauge not reading correctly.
Does the vehicle have a trip meter with mpg?

 

[Rbaker]

No without a doubt it used fuel like pouring it out and then back to normal as soon as trailer is unhooked

 

[Rbaker]

I have had many vehicles and towed every kind of trailer and have never had anything use fuel like this especially with such a small load.