We are 102,000+ car owners sharing real-world car information.
Sorry, we don't yet have gas mileage data for the Sierra HD.
None of our members have yet commented on the real gas mileage of the GMC Sierra HD.
Be the first!
Unlike other fuel economy surveys, TrueDelta's Real-World Gas Mileage Survey includes questions about how and
where a car was driven. So you can get an idea of the GMC Sierra HD's
real-world MPG based on how and where you drive a car.