Mileage question???????
Thread Starter
Intermediate
Joined: Feb 2004
Posts: 43
Likes: 1
From: hendersonville nc
Mileage question???????
I've had my '04 C5 for 4 months now. I drive 50 miles to
work every day, all highway. When I first started I got
27 MPG. Since my oil change I'm getting 24. Same driving
habits (I cruise at 55-60 mph)
My '01 also got 27mpg. Anyone have any answers?
Thanks in advance
work every day, all highway. When I first started I got
27 MPG. Since my oil change I'm getting 24. Same driving
habits (I cruise at 55-60 mph)
My '01 also got 27mpg. Anyone have any answers?
Thanks in advance
Le Mans Master
Joined: Mar 2004
Posts: 5,562
Likes: 5
From: South East coast Florida
When they change the oil, they must idle the car for some time period to check for leaks. This reduces the average MPG by a substantial amount. Does take a fair amount of driving to build it back up.
Not sure how long ago you got the oil changed or if you reset the AVG MPG when you got the car back. Best I can comeup with at this time.
Not sure how long ago you got the oil changed or if you reset the AVG MPG when you got the car back. Best I can comeup with at this time.
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Weather conditions and traffic flow will also affect it. Saw you haven't reset the MPG indicator - that would help you see if you are still getting the higher MPG.
Race Director
Joined: Sep 2004
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I just thought of something:
Are you sure they used 5-30 oil?? If they used a higher viscosity when they changed your oil your mileage could suffer a little bit because the oil takes longer to flow readily through the engine causing reduced fuel mileage for the first few miles.
A long shot but just a thought.
Are you sure they used 5-30 oil?? If they used a higher viscosity when they changed your oil your mileage could suffer a little bit because the oil takes longer to flow readily through the engine causing reduced fuel mileage for the first few miles.
A long shot but just a thought.
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Le Mans Master
Joined: Mar 2004
Posts: 5,562
Likes: 5
From: South East coast Florida
Originally Posted by lvvette777
I just thought of something:
Are you sure they used 5-30 oil?? If they used a higher viscosity when they changed your oil your mileage could suffer a little bit because the oil takes longer to flow readily through the engine causing reduced fuel mileage for the first few miles.
A long shot but just a thought.
Are you sure they used 5-30 oil?? If they used a higher viscosity when they changed your oil your mileage could suffer a little bit because the oil takes longer to flow readily through the engine causing reduced fuel mileage for the first few miles.
A long shot but just a thought.
