Just a curious question. Could a bad wheel bearing cause a drop in MPG's? I would assume due to increased rolling resistance? I ask because a few days ago, with a bad wheel bearing I drove about 200 miles and got about 32 mpg's. Today, after replacing the wheel bearing I drove about 250 miles and got 38 mpg's. I don't think I was driving much differently, about the same speed, same road. Weather was fairly close to what it was. About the same temp, maybe a little less humidity. Winds weren't quite a strong today as last time.
So, could a bad wheel bearing cause an MPG's decrease? I would assume the decrease in wind helped a little, but there really wasn't much of a difference in the other aspects of weather. Could just be a fluke?
If there is a better forum for this, by all means move it, it was just the best place I thought it fit.
No, it wouldnt.
To calcurate fuel mileage correctly you need to do the following.
Fill the vehicle up with gas. Drive the vehicle for the entire tank, 1 or 2 gallons left.
Take the numer of gallons used, say 10, and divide by the number of miles say 300. 300/10 = 30mpg
Actually when I worked for Nissan, and they had customers with a fuel mileage complaint, they made them fill it up and empty it three times to get it, if their complaint was low gas mileage
- 2004 Cavalier - 124k, owned since new
I know how to calculate MPG's. I reset my trip after I fill up. I drive until I hit aprox 1/2 tank, then fill up again. I then divide the trip miles by whatever I put in the tank. I know the way I do it isn't perfectly accurate, but an 8 mpg difference seemed kinda drastic.
I'm not worried about it. I'm keeping my eye on the MPG's, and I check them every time I fill up. A decrease would indicated a problem, so I like to keep up on checking it.
It was just a curious question.
Logically, i see no reason why not.
But realistically, 8MPG (accurate or not), i'm not so sure.
Yeah I wans't thinking that it would be that drastic.
I'm going to get a set of base numbers, city driving, city/highway driving, and highway driving and see if they stay constant. We'll see what happens.
I may be mistaken, but the first 200 miles that I got 32 mpg's with may have had some city driving mixed in. The 250 miles was all highway. Filled up right before the highway, and filled up again on the highway.
I guess we'll see what's going on when I get my base set of numbers.
How bad was this wheel bearing?
There wasn't much play, but it was very rough.
