Why do compact crossovers have small fuel tanks

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I’m curious as to why small crossovers have tiny fuel tanks. I’ve seen the Buick Envista and that vehicle is plenty big enough to accomodate a 15-16 gallon tank to enable it to go at least 600 miles if not more at the 32mpg interstate rating. Why do automakers keep putting 11-13 gallon tanks in vehicles that only allow it to go around 300 miles on a tank. Wouldn’t the bigger fuel tank be the better and more sensible option?

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13 Answers

Anonymous 0 Comments

If it was something the market wanted, the automakers would add larger tanks. But their sales and market research likely indicates a bigger tank is not a significant selling point. They’re not making the costly design, engineering, factory retooling, and safety testing changes that adding a larger tank would require when they don’t see it improving profitability.

And your math doesn’t math – adding 3-5 gallons to an 11-13 gallon tank doesn’t more than double the range. 32 mpg times 16 gallons is just a bit above 500 miles, not at least 600 if not more.

Anonymous 0 Comments

I think it would be easy to fit larger tanks. But there is probably no need for it (except maybe if you try to cross a desert or such). I think the average distance traveled per day is about 25km to 50km. Most cars have a range which well exceeds this. I live in Europe and I think I barley ever need to drive more than 5 minutes to find a gas station.
I mean, even when the empty tank light goes on, most cars probably run another 100km (which suffices to reach a few thousand gas stations).

Anonymous 0 Comments

Compact crossovers are primarily aimed at suburban commuters, perhaps with a young child or two. They’re not exactly long distance touring machines.

No doubt the manufacturers have done their research and figured out that their target market simply don’t want or need greater range. A smaller tank allows a larger cargo area or more passenger space, which are higher priorities.

Anonymous 0 Comments

Tank size and the fuel in impact the total vehicle weight, inclusive of fuel, cargo and passengers. Gasoline is about 6 pounds a gallon. Plus the weight and size of a larger tank. A larger tank would require either a longer and heavier car, or less cargo space. Everything is a trade off.

More fuel, less fuel efficiency, less cargo space. Average daily commute is about 40 miles roundtrip. A 300 mile range is enough cover about a week’s worth of driving at least for urban and suburban commuters. Could they put a massive 25 gallon tank in a car? Sure. Look up the old ford crown victoria or the 70s era Ford Pinto. Both of those cars had design flaws in the fuel tank that caused the tank to rupture and spray fuel into the passenger compartment in accidents.

A larger tank might not fit under the car, and it might need to be placed higher up into the trunk area increasing the risk that fuel could be sprayed into the passenger area.

Anonymous 0 Comments

40L petrol tanks are normal here in the UK (and I assume Europe).

Why carry all that extra fuel around when you’re usually at most half hour drive from a pump.

Anonymous 0 Comments

Companies do research into what consumers look for. Every click on their website for a car, how long people spend looking at each page. They look at what reviews say, they ask salespeople what buyers ask about, etc 

People buying compact cars likely want cargo space. Picture the size of a 5 gallon bucket, now take that away from the storage area.

A small tank costs less to fill than a large one. Even though math says there isn’t a difference in fuel economy not everyone is good at math. There may be some psychology that consumers think they are better off spending less to ‘fill up the tank’.

Anonymous 0 Comments

The first gen Subaru Crosstrek/XV has a small fuel tank, and an engine that’s undersized for the application. The engine specifies the use of super-thin 0W20 oil.
I believe that the priority behind all of these decisions was chasing emissions ratings. The few cases of people swapping in the larger 2.5l engine have shown better fuel economy due to not having to work the engine so hard. The manual version chews clutches because the driver is forced to compensate for the lack of torque with higher revving. The thin oil is more prone to finding its way past piston rings and leaks, but it does reduce mechanical drag and therefore lower emissions. A larger fuel tank is heavier when full, and would also affect the rating.

Just my personal thoughts.

Anonymous 0 Comments

Consumers aren’t demanding 600-mi range. It costs more to make a larger fuel tank, it weighs more when tank is full, it takes up volume within the vehicle’s frame, it costs more to fill up…

Anonymous 0 Comments

I need some math on how a 13 gallon tank would have a range of 300 miles and a 15 gallon tank would have a range of 600 miles. Make it make sense.

Anonymous 0 Comments

Do you really drive 600 miles on road trips without stopping? Often enough that it would influence your choice of vehicle?

A larger gas tank would probably depress gas mileage, due to more weight being carried around, and take up cargo room.