Skip the auto shop - Our mechanics make house calls

Q: My truck uses a lot of gas

asked by on

I installed an after market muffler onto my truck. The first couple of months was fine but then I realized my truck was using too much fuel. I fill it up and about 5 days it's all gone. What's the issue ? Thank you

My car has 25000 miles.
My car has an automatic transmission.

A: Hey there. There are many versions of your ...

Hey there. There are many versions of your vehicle, so the mileage varies between 17 to 20 (combined city/highway) depending on the version. See fueleconomy.gov to determine what the rated mileage is for your version of the vehicle. The flex fuel version (using E-85) of your vehicle will have much lower mileage, reflecting the much lower energy content of the fuel. If after measuring your actual fuel economy it is 10% or more below the government published rating, then you have a problem.

Whether the degradation is due to an aftermarket muffler or not is not clear. You would have to talk to the manufacturer about their product specifications and how such compares to OEM. It is technically possible to measure back pressure in the exhaust system if the need arose. But aftermarket exhausts are required to allow the vehicle to function per government mandated fuel economy standards. If these aftermarket parts didn’t, and caused a degradation in your results, that would be a problem. In your circumstance, I would first carefully measure the actual fuel economy you are getting over a period of about a month. Simply compare those data with the rated (expected) performance of the vehicle. If the values are within 10%, that is within an acceptable range due to differences in climate, elevation, driving characteristics, and variances in loads that are carried in these trucks. If you would like to get the truck’s gas usage inspected by an expert, a certified professional from YourMechanic can come to your car’s location to have this examined.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: My car has low oil pressure. I've already changed the oil pressure sensor 3 times.

If you have replaced the sensor three times and it did not fix the problem, then you may have problems with the oil pressure being low at idle due to wear in the engine bearings. The reason it would be...

Q: Exhaust muffler, front rotor

Brake rotors are replaced in pairs because if you put new brake parts, such as a rotor, on one side of the car only, when you apply the brakes the car will pull to one side. Also, if you install...

Q: Why are my signal mirrors flashing wile my truck is turned off its just the blinker in both mirrors, mirrors are factory

Hello. If any sort of lights keep flashing when the vehicle is turned off then there is likely some sort of electrical issue present in the vehicle. A few common causes for lighting malfunctions are a faulty turn signal switch,...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...