# Odometer **URL:** \ **Category:** Factual Questions\ **Created:** [June 4, 2013, 8:11pm UTC](https://boards.straightdope.com/t/odometer/660149 "2013-06-04T20:11:31Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![anfurnne](https://avatars.discourse-cdn.com/v4/letter/a/f05b48/32.png) [@anfurnne](https://boards.straightdope.com/u/anfurnne)\ **Post date:** [June 4, 2013, 8:11pm UTC](https://boards.straightdope.com/t/odometer/660149/1 "2013-06-04T20:11:31Z")
I have a 92 Camry. My insurance company ask for my mileage every year. This year I noticed I drove 2543 miles. No way I drove that many. It comes to roughly a little over 200 miles a month. On average I don’t drive more then 3-4 miles a day m-f. Can a odometer fail and show more or less then the actual miles driven? How to check if an odometer is working? Thank you. ---
**Author:** ![JerrySTL](https://avatars.discourse-cdn.com/v4/letter/j/e274bd/32.png) [@JerrySTL](https://boards.straightdope.com/u/JerrySTL)\ **Post date:** [June 4, 2013, 8:19pm UTC](https://boards.straightdope.com/t/odometer/660149/2 "2013-06-04T20:19:31Z")
Most Interstate highways have mileage markers. You could compare it to your odo as you pass them. If it has a trip meter, you could set it to zero and also check against the mile markers. If you know of someone with a car GPS, they can also track mileage. Have you put on new tires in the last year or so? If they put on smaller than normal tires, that would show up with more mileage. Do you have kids that drive; lend it to someone for a few days; or have it in a shop overnight? Someone could have taken a road trip. Then it could be a matter of your math. Are you sure of last year’s mileage? Could the miles been from a couple of years ago? ---
**Author:** ![TimeWinder](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)\ **Post date:** [June 4, 2013, 8:20pm UTC](https://boards.straightdope.com/t/odometer/660149/3 "2013-06-04T20:20:39Z")
Use Bing/Google maps to plot out a ten mile trip. Drive it. See if odometer registers ten miles. 4 miles/day x 250 days/year is 1000 miles, so you’re claiming that the odometer is off by a factor of at least two – even a short drive should show it. That said, 2500 miles a year is a very, very, very low mileage for a year for a commuter car, american average is something like 15,000 per year (which is why leases are always for 10 or 12K, with overage fees). I’d bet you’re driving a longer distance than you think you are. ---
**Author:** ![Pasta](https://avatars.discourse-cdn.com/v4/letter/p/ecccb3/32.png) [@Pasta](https://boards.straightdope.com/u/Pasta)\ **Post date:** [June 4, 2013, 8:29pm UTC](https://boards.straightdope.com/t/odometer/660149/4 "2013-06-04T20:29:56Z")
I assume that’s 3 or 4 miles round-trip? Are you counting the rare trips to drop someone off at the airport, to take a trip to the big city, to head to the beach? If you really only drive 3 or 4 miles in a normal day, longer rare trips could easily be the dominant part of your mileage, especially if they aren’t as rare as you think. Even if you only make longer trips (say, 50 miles) every six weeks, that’s enough to make up the difference. ---
**Author:** ![Anaamika](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@Anaamika](https://boards.straightdope.com/u/Anaamika)\ **Post date:** [June 4, 2013, 8:48pm UTC](https://boards.straightdope.com/t/odometer/660149/5 "2013-06-04T20:48:10Z")
> [@TimeWinder](#): > > Use Bing/Google maps to plot out a ten mile trip. Drive it. See if odometer registers ten miles. 4 miles/day x 250 days/year is 1000 miles, so you’re claiming that the odometer is off by a factor of at least two – even a short drive should show it. > > That said, 2500 miles a year is a very, very, very low mileage for a year for a commuter car, american average is something like 15,000 per year (which is why leases are always for 10 or 12K, with overage fees). I’d bet you’re driving a longer distance than you think you are. Agreed 100%. Even when I was literally doing nothing but driving my car to work and home, using the (newer) car for every thing else, I was doing about 3000 miles in a year. ---
**Author:** ![yearofglad](https://avatars.discourse-cdn.com/v4/letter/y/b782af/32.png) [@yearofglad](https://boards.straightdope.com/u/yearofglad)\ **Post date:** [June 4, 2013, 9:10pm UTC](https://boards.straightdope.com/t/odometer/660149/6 "2013-06-04T21:10:14Z")
I work from home and drive my car three times a week AT MOST, and never on long trips - always within the city. And I drive about 2,000 miles a year. My guess is, as the other posters said, you are putting on more miles than you think you are. They add up fast. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [June 5, 2013, 3:01pm UTC](https://boards.straightdope.com/t/odometer/660149/7 "2013-06-05T15:01:46Z")
I’m not familiar with the 92 Camry. Does it have an electronic digital odometer? I’ve never been sure how much to trust those. Is the cumulative mileage just stored in some non-volatile memory somewhere? If so, how well protected is it from _ever_ getting glitched? Is there also a mechanical odometer somewhere in the car, even if it’s behind the scenes? It seems odd to me if regulations allow cars to exist without a mechanical odometer somewhere. (For example, gas pumps at gas stations appear to be all-digital these days, but in fact they have a mechanical odometer-like counter in them that tracks the total cumulative gallons pumped. In many pumps they are visible, but small and inconspicuous.) ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 5, 2013, 4:12pm UTC](https://boards.straightdope.com/t/odometer/660149/8 "2013-06-05T16:12:20Z")
> [@Senegoid](#): > > I’m not familiar with the 92 Camry. Does it have an electronic digital odometer? I’ve never been sure how much to trust those. Is the cumulative mileage just stored in some non-volatile memory somewhere? If so, how well protected is it from _ever_ getting glitched? > > Is there also a mechanical odometer somewhere in the car, even if it’s behind the scenes? It seems odd to me if regulations allow cars to exist without a mechanical odometer somewhere. > > (For example, gas pumps at gas stations appear to be all-digital these days, but in fact they have a mechanical odometer-like counter in them that tracks the total cumulative gallons pumped. In many pumps they are visible, but small and inconspicuous.) The Odo chip is _ **incredibly** _ reliable. It may be the only piece of electronics in the car that actually has to pass federal reliability standards. I used to work for a company that made these chips, and they went through the most stringent testing of any product they made. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [June 5, 2013, 4:33pm UTC](https://boards.straightdope.com/t/odometer/660149/9 "2013-06-05T16:33:49Z")
Airbag control systems have to pass NTHSA testing as well. > [@Senegoid](#): > > I’m not familiar with the 92 Camry. Does it have an electronic digital odometer? I’ve never been sure how much to trust those. The XV10 Camrys had analog odometers. As far as trusting digital odometers, I trust them a million times more than analog ones; you can’t “clock” them (wind them back). ---
**Author:** ![tomndebb](https://avatars.discourse-cdn.com/v4/letter/t/b9e5f3/32.png) [@tomndebb](https://boards.straightdope.com/u/tomndebb)\ **Post date:** [June 5, 2013, 4:48pm UTC](https://boards.straightdope.com/t/odometer/660149/10 "2013-06-05T16:48:11Z")
> [@anfurnne](#): > > I have a 92 Camry. My insurance company ask for my mileage every year. This year I noticed I drove 2543 miles. No way I drove that many. It comes to roughly a little over 200 miles a month. On average I don’t drive more then 3-4 miles a day m-f. Can a odometer fail and show more or less then the actual miles driven? How to check if an odometer is working? Thank you. Is there a teen in the house? 😛 ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [June 5, 2013, 5:00pm UTC](https://boards.straightdope.com/t/odometer/660149/11 "2013-06-05T17:00:34Z")
I agree with others. You are putting the miles on without realizing it. It is 2.2 miles to my office. (More of course if I swing by the grocery store or another errand on the way home). The car is 10 years old and has just over 30,000 miles on it. I can’t possibly have driven that far, but I’ve “clocked” the odometer and it’s accurate. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [June 5, 2013, 5:03pm UTC](https://boards.straightdope.com/t/odometer/660149/12 "2013-06-05T17:03:31Z")
For an odometer to register twice the actual miles driven while the speedometer registers normally is extremely unlikely. I’ve never run across even a hint of such a thing in a 40 year career in auto repair. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [June 5, 2013, 5:08pm UTC](https://boards.straightdope.com/t/odometer/660149/13 "2013-06-05T17:08:14Z")
In fairness, if it did happen, how would you know? 😉 ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [June 5, 2013, 5:09pm UTC](https://boards.straightdope.com/t/odometer/660149/14 "2013-06-05T17:09:12Z")
> [@Really\_Not\_All\_That\_Bright](#): > > The XV10 Camrys had analog odometers. As far as trusting digital odometers, I trust them a million times more than analog ones; you can’t “clock” them (wind them back). This might be a bit of a tangent, but no way. You might have been able to trust digital odometers back when only an expensive dealer-only tool could change the readings, but these days… well, just google “odometer correction tool” and see for yourself. For most makes and models, you can get one for less than $100. Now consider that analog odometers since the 70’s were designed in such a way that if they were rolled backwards, the numbers wouldn’t line up. So they _were_ virtually tamper-proof. The digital odometers are more reliable mechanically, but they’re a step backwards in terms of fraud prevention. As for the OP, teenagers was my guess as well. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [June 5, 2013, 5:16pm UTC](https://boards.straightdope.com/t/odometer/660149/15 "2013-06-05T17:16:18Z")
> [@GreasyJack](#): > > This might be a bit of a tangent, but no way. You might have been able to trust digital odometers back when only an expensive dealer-only tool could change the readings, but these days… well, just google “odometer correction tool” and see for yourself. For most makes and models, you can get one for less than $100. _googles_ Aw, crap. Ignorance fought. :eek: ---
**Author:** ![anfurnne](https://avatars.discourse-cdn.com/v4/letter/a/f05b48/32.png) [@anfurnne](https://boards.straightdope.com/u/anfurnne)\ **Post date:** [June 10, 2013, 6:10pm UTC](https://boards.straightdope.com/t/odometer/660149/16 "2013-06-10T18:10:38Z")
Thank you all. Because of the price of gas I don’t take long drives. The 4-5 mile a day is round trip. The kids school is less then a mile away but I drive them to school anyways because of all the molesters that keep getting out of jail. I just can’t believe I drive that much, it don’t seem like I do. I will try the tips you gave me and I will see if I drive that much. Thanks ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [June 10, 2013, 6:25pm UTC](https://boards.straightdope.com/t/odometer/660149/17 "2013-06-10T18:25:28Z")
> [@GreasyJack](#): > > Now consider that analog odometers since the 70’s were designed in such a way that if they were rolled backwards, the numbers wouldn’t line up. So they _were_ virtually tamper-proof. Not where I come from - the crooks just wind them forward instead. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [June 10, 2013, 6:27pm UTC](https://boards.straightdope.com/t/odometer/660149/18 "2013-06-10T18:27:20Z")
How much do you spend on gas? According to [this](http://www.ehow.com/list_7577018_1992-toyota-camry-specifications.html), your car has a 21 mpg fuel economy (city) and a 18.5 gallon fuel tank. So if you were really only driving 4 miles per day on average, you should only be using 5.7 gallons per month, and a tank of gas should last almost 3 months. ---
**Author:** ![dracoi](https://avatars.discourse-cdn.com/v4/letter/d/90db22/32.png) [@dracoi](https://boards.straightdope.com/u/dracoi)\ **Post date:** [June 10, 2013, 6:58pm UTC](https://boards.straightdope.com/t/odometer/660149/19 "2013-06-10T18:58:55Z")
> [@anfurnne](#): > > Thank you all. Because of the price of gas I don’t take long drives. The 4-5 mile a day is round trip. The kids school is less then a mile away but I drive them to school anyways because of all the molesters that keep getting out of jail. I just can’t believe I drive that much, it don’t seem like I do. I will try the tips you gave me and I will see if I drive that much. Thanks I’ll bet you it adds up more quickly than you think. My wife and I track mileage for business, and it’s not unusual to have a couple of extra miles on top of our GPS/Google Map when all is said and done. For example, you can put on an extra mile just circling a parking lot looking for a spot. My wife can put on 40 miles in a day of running errands on the weekends. None of them are long trips individually, but there are a lot of stops a few miles apart each time. ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [June 10, 2013, 7:18pm UTC](https://boards.straightdope.com/t/odometer/660149/20 "2013-06-10T19:18:54Z")
> [@bob\_2](#): > > Not where I come from - the crooks just wind them forward instead. It’s not so much which direction you go, it’s when you open it up and fiddle with the numbers. If you actually run the odometer with a drill or something, I _think_ you can run it backwards or forwards and numbers will still line up, but you’d have to be pretty patient rolling them off at 120 miles per hour or so. > [@scr4](#): > > How much do you spend on gas? According to [this](http://www.ehow.com/list_7577018_1992-toyota-camry-specifications.html), your car has a 21 mpg fuel economy (city) and a 18.5 gallon fuel tank. So if you were really only driving 4 miles per day on average, you should only be using 5.7 gallons per month, and a tank of gas should last almost 3 months. The ridiculously short trips the OP is taking are the worst driving you can do for fuel economy-- they may not even be getting 21 mpg. [Next page](https://boards.straightdope.com/t/odometer/660149.md?page=2)