Classic/Antique Car Repair: gas mileage, rear axle ratio, odometer reading

Question
QUESTION: I have a 1952 Chevrolet pickup with a single barrel carb on the engine....it is a 1956 235 cubic inch....I get around 12 to 15 miles per gallon....people are surprised that I get such low mileage...I simply cannot remember in those days what kind of mileage I got from the cars....I can not remember it really being an issue...what should I expect?  Thanks...Glenn

ANSWER: What series is your pick up? Is it a 1/2 ton with the light duty rear axle and a 3 speed transmission? If it is a heavy duty what we used to call a 3/4 ton with a 4 speed it could have a real low gear rear axle that would reduce fuel economy. Let me know.
Brad

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QUESTION: It is a 3100; 1/2 ton with a three speed.  Nothing special.

Answer
That truck when delivered from the factory had a 4.11:1 rear axle ratio and 6.70X15 tires. The 4.11 is not an economy axle and was used to give the little 216 cubic inch 6 cylinder enough poop to carry a half ton plus the 2600 pound weight of the truck. Now if the tire size has been changed that could upset the odometer reading. Have you checked the odometer against a measured mile? Let me know and we can go from there.
Brad