Horrible Gas mileage
Ok.. so I know fuel mileage is probably the biggest shock most RV'ers experience, shortly after they shell out the big bucks for their rig. I have a 2011 GMC Silverado, short bed, 5.3L, 3.73 gears, t...
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Your mileage is within range, depending on how fast you drive. You'll do better if you slow down. New tires won't make a measurable difference. A new truck will probably make some difference, but not enough to justify the expense (unless you just want to use it as an excuse to get a new truck).
FWIW - I get 11 while towing (according to pump measurements on a 1600 mile trip - my Sienna is a base model that doesn't have an average mpg display).
Also FWIW - the computer really is right - it controls the fuel flow to the fuel injectors very precisely and knows exactly how much was used. If you think it's wrong because you were doing measurements between two fill-ups and using the second pump and mileage to calculate, you're basing that off the assumption that both pumps shut off at the exact same fill level and that both pumps gas flow gauge is accurate (it's likely close). There's no reason to precisely calibrate when pumps shut off, so they don't. Chances are the second pump shut off later than the first and put more gas into the tank.
FWIW - I get 11 while towing (according to pump measurements on a 1600 mile trip - my Sienna is a base model that doesn't have an average mpg display).
Also FWIW - the computer really is right - it controls the fuel flow to the fuel injectors very precisely and knows exactly how much was used. If you think it's wrong because you were doing measurements between two fill-ups and using the second pump and mileage to calculate, you're basing that off the assumption that both pumps shut off at the exact same fill level and that both pumps gas flow gauge is accurate (it's likely close). There's no reason to precisely calibrate when pumps shut off, so they don't. Chances are the second pump shut off later than the first and put more gas into the tank.
