# L vs R side for gas cap on cars in US **URL:** \ **Category:** Factual Questions\ **Created:** [January 1, 2009, 12:21am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421 "2009-01-01T00:21:58Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [January 1, 2009, 12:21am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/1 "2009-01-01T00:21:58Z")
What percentage of autos sold in the US have the gas cap on the driver’s (left side)? Left is the default side in my mind; every car I’ve owned has had it on that side. But every once in a while, when driving a rental care, I discover only after pulling up to the pump that the cap is on the _right_ side! :smack: Any rhyme or reason for such placement? ---
**Author:** ![Todderbob](https://avatars.discourse-cdn.com/v4/letter/t/e47774/32.png) [@Todderbob](https://boards.straightdope.com/u/Todderbob)\ **Post date:** [January 1, 2009, 12:24am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/2 "2009-01-01T00:24:20Z")
It’s to mess with our heads. That’s the only logical explanation I’ve ever been able to come up with. ---
**Author:** ![FarmerChick](https://avatars.discourse-cdn.com/v4/letter/f/a9a28c/32.png) [@FarmerChick](https://boards.straightdope.com/u/FarmerChick)\ **Post date:** [January 1, 2009, 12:29am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/3 "2009-01-01T00:29:05Z")
Interesting little fact, you know on the gas gauge, when you see the little pump? Whichever side of the gauge it is on, that’s the side of the car your gas cap is on. (Damn, did that make sense?) ---
**Author:** ![Hunter\_Hawk](https://avatars.discourse-cdn.com/v4/letter/h/50afbb/32.png) [@Hunter\_Hawk](https://boards.straightdope.com/u/Hunter_Hawk)\ **Post date:** [January 1, 2009, 12:41am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/4 "2009-01-01T00:41:39Z")
IMHO response: I personally strongly prefer the cap to be on the passenger side. I can pull up close to the pump and not have to worry about dinging my door when I get out. It also makes it easier to walk around the car if I want to wash my windows while the gas is pumping. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [January 1, 2009, 12:57am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/5 "2009-01-01T00:57:58Z")
There’s no logic, really. There’s not even consistency amongst models produced by a single manufacturer. There _may_ be some underlying engineering reason for a model to have it on one side or the other, but I’ve never heard of one. The arguments I’ve heard for putting it on the passenger side include those that **Hunter** has mentioned, as well as safety for when you have to refill your tank on the side of the road (the bulk of the car will be between you and the road). Putting it on the driver’s side is endorsed by Click & Clack who’ve started [Fuel Opening On the Left Side.](http://www.cartalk.com/content/columns/Archive/1994/October/12.html)😃 Personally, I like what they did on a number of models in the 60s & 70s, where the gas cap was behind the rear license plate. That way there was no futzing around with making sure you’d pulled up to the pump on the right side. ---
**Author:** ![goransmom](https://avatars.discourse-cdn.com/v4/letter/g/f07891/32.png) [@goransmom](https://boards.straightdope.com/u/goransmom)\ **Post date:** [January 1, 2009, 1:01am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/6 "2009-01-01T01:01:08Z")
My VW salesman (when he learned I was interested in safety features) said that all VWs have the gas tank on the passenger side so that if you’re filling up on the side of the road, you’re away from the traffic. I think it’s safer not to actually run out of gas… ---
**Author:** ![Noel\_Prosequi](https://avatars.discourse-cdn.com/v4/letter/n/b19c9b/32.png) [@Noel\_Prosequi](https://boards.straightdope.com/u/Noel_Prosequi)\ **Post date:** [January 1, 2009, 1:02am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/7 "2009-01-01T01:02:59Z")
There must be a convention about this, otherwise the power of standards would have mandated that one side would be universal. I suspect that the fact that caps can be found on both sides is a consequence of petral station layouts. You have to have bowsers in the middle of concourses. If all the caps were on the one side, the potential efficiency of having pumps on both sides of the bowsers would, inconveniently, be lost. ---
**Author:** ![74westy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/74westy/32/3950_2.png) [@74westy](https://boards.straightdope.com/u/74westy)\ **Post date:** [January 1, 2009, 1:03am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/8 "2009-01-01T01:03:49Z")
> [@FarmerChick](#): > > Interesting little fact, you know on the gas gauge, when you see the little pump? Whichever side of the gauge it is on, that’s the side of the car your gas cap is on. (Damn, did that make sense?) Unfortunately [snopes](http://www.snopes.com/autos/techno/icon.asp) won’t back you up. I’ve always thought the proper place for tank filler was inside the[left rear tail fin](http://www.worldofstock.com/closeups/TRC4160.php) but maybe Tuckerfan knows of a better hidden location in the left rear fender. ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [January 1, 2009, 1:20am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/9 "2009-01-01T01:20:15Z")
> [@Noel\_Prosequi](#): > > There must be a convention about this, otherwise the power of standards would have mandated that one side would be universal. It’s however it fits best with the car design. One pretty good general rule is that if the car has a single tailpipe the filler cap will be on the opposite side of the car. I’m not sure why there would need to be a standard. And trucks with dual tanks often have dual filler doors, or at least they did. Having the gas filler behind he rear license plate is more dangerous in the event of a rear collision. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [January 1, 2009, 1:22am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/10 "2009-01-01T01:22:34Z")
The gas guages on many car models do have a gas pump icon and a pointer or arrow to left or right. If present, the pointer does point to the filler side. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [January 1, 2009, 1:32am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/11 "2009-01-01T01:32:56Z")
> [@Noel\_Prosequi](#): > > There must be a convention about this, otherwise the power of standards would have mandated that one side would be universal. I suspect that the fact that caps can be found on both sides is a consequence of petral station layouts. You have to have bowsers in the middle of concourses. If all the caps were on the one side, the potential efficiency of having pumps on both sides of the bowsers would, inconveniently, be lost. Only if cars could only pull in one side of the station. And you over estimate the driving power of standards. Cars were _supposed_ to switch to 42V batteries years ago, but because nobody can agree on anything, we’re stuck with 12V systems, like we’ve had since the 1960s. > [@74westy](#): > > I’ve always thought the proper place for tank filler was inside the[left rear tail fin](http://www.worldofstock.com/closeups/TRC4160.php) but maybe Tuckerfan knows of a better hidden location in the left rear fender. You mean like [this?](http://www.oldcarandtruckpictures.com/Tucker/1948TuckerGasCap.jpg) Only about the first 25 models had that set up. The rest [had it on the driver’s side fender](http://www.oldcarandtruckpictures.com/Tucker/GilmoreCarMuseumsTucker1047.jpg) as the gas tank was shifted to the front, in order to improve the weight balance of the cars. > [@Telemark](#): > > Having the gas filler behind he rear license plate is more dangerous in the event of a rear collision. It wouldn’t take that much work to have the gas filler back there and have it be just as safe as being mounted on one side or the other. Foam filled tanks (like are used on race cars), as well as a breakaway filler tube would go a long way to making it safe (and those things would improve the safety on side fillers, as well). ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [January 1, 2009, 1:49am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/12 "2009-01-01T01:49:32Z")
> [@74westy](#): > > I’ve always thought the proper place for tank filler was inside the[left rear tail fin](http://www.worldofstock.com/closeups/TRC4160.php) but maybe Tuckerfan knows of a better hidden location in the left rear fender. My mom had that car. She loved confusing gas station attendants with it. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [January 1, 2009, 1:55am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/13 "2009-01-01T01:55:09Z")
> [@FarmerChick](#): > > Interesting little fact, you know on the gas gauge, when you see the little pump? Whichever side of the gauge it is on, that’s the side of the car your gas cap is on. (Damn, did that make sense?) This is not true for my 1994 Honda Accord. The gas cap is on the left/driver’s side, while the icon on the dashboard shows the pump on the right/passenger side. ---
**Author:** ![Yorikke](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yorikke/32/4335_2.png) [@Yorikke](https://boards.straightdope.com/u/Yorikke)\ **Post date:** [January 1, 2009, 1:57am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/14 "2009-01-01T01:57:36Z")
I work at a gas station. I think it’s utterly random. Joe ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [January 1, 2009, 1:58am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/15 "2009-01-01T01:58:31Z")
> [@Tuckerfan](#): > > It wouldn’t take that much work to have the gas filler back there and have it be just as safe as being mounted on one side or the other. Foam filled tanks (like are used on race cars), as well as a breakaway filler tube would go a long way to making it safe (and those things would improve the safety on side fillers, as well). After the Pinto Car-B-Que disaster, I doubt you will ever see a rear mounted filler neck from any car maker that sells in this country. Regardless of how the tank and filler neck are constructed, this arrangement would have lawyers drooling in anticipation. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [January 1, 2009, 2:00am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/16 "2009-01-01T02:00:49Z")
> [@FarmerChick](#): > > Interesting little fact, you know on the gas gauge, when you see the little pump? Whichever side of the gauge it is on, that’s the side of the car your gas cap is on. (Damn, did that make sense?) On my 06 Civic the gas cap is on the driver side, but the guage is on the right side (with an arrow pointing to the left). The only thing I’ve ever heard, and I have NO idea whatsoever if there’s any truth at all to it is that it’s on the opposite side of the exhaust pipe. ---
**Author:** ![Mahaloth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mahaloth/32/1079_2.png) [@Mahaloth](https://boards.straightdope.com/u/Mahaloth)\ **Post date:** [January 1, 2009, 2:03am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/17 "2009-01-01T02:03:26Z")
> [@Tuckerfan](#): > > Personally, I like what they did on a number of models in the 60s & 70s, where the gas cap was behind the rear license plate. That way there was no futzing around with making sure you’d pulled up to the pump on the right side. My Grandma’s car was like that. It was cool! 🆒 😃 ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [January 1, 2009, 2:07am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/18 "2009-01-01T02:07:57Z")
> [@Rick](#): > > After the Pinto Car-B-Que disaster, I doubt you will ever see a rear mounted filler neck from any car maker that sells in this country. Regardless of how the tank and filler neck are constructed, this arrangement would have lawyers drooling in anticipation. The irony, of course, is that when the Pinto was designed, it was going to have a foam filled tanks and airbags, so it would have been quite safe. Ford, however, figured that it’d be cheaper to pay lawsuits than to actually build the cars that way. As it turned out, Ford didn’t have to pay anything out, as they won their cases. (The SNL Weekend Update segment where Ralph Nader rants about this is pretty hysterical, even if you think Nader’s a total nutjob.) ---
**Author:** ![JKilez](https://avatars.discourse-cdn.com/v4/letter/j/e5b9ba/32.png) [@JKilez](https://boards.straightdope.com/u/JKilez)\ **Post date:** [January 1, 2009, 3:11am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/19 "2009-01-01T03:11:30Z")
No, no, no. The argument should not be left or right, it should be front or back. Everyone knows that real cars have their gas caps on the left front fender where the driver can keep an eye on them. 😃 ---
**Author:** ![Fubaya](https://avatars.discourse-cdn.com/v4/letter/f/c2a13f/32.png) [@Fubaya](https://boards.straightdope.com/u/Fubaya)\ **Post date:** [January 1, 2009, 3:31am UTC](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421/20 "2009-01-01T03:31:38Z")
> [@goransmom](#): > > My VW salesman (when he learned I was interested in safety features) said that all VWs have the gas tank on the passenger side so that if you’re filling up on the side of the road, you’re away from the traffic. > > I think it’s safer not to actually run out of gas… That’s probably true but the VW Routan has it on the left. Maybe because it’s a minivan and it’s too far to walk all the way around. [Next page](https://boards.straightdope.com/t/l-vs-r-side-for-gas-cap-on-cars-in-us/479421.md?page=2)