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Fuel Filler door

Fuel Filler door

Fuel Filler door

I am a reasonable intelligent person, but for the life of me I can not figure out why the fuel filler door is located on some cars on the passenger side.  My wife who is blonde keeps asking me that same question, and I have no answer for her.  In this time of huge filling stations, it only adds to the confussion with some cars pulling in one way and the others the opposite way. It would seem that a simple enough reason to keep it on the left side would be for driver convenience.  Does anyone have a bonifide answer to this????

RE: Fuel Filler door

More or less for the same reason you are allowed to buy a green car or a yellow car. If you don't like it , buy something else!


Greg Locock

RE: Fuel Filler door

Unless of course you live in England, Oz, New Zealand or Japan.

Other than the increased risk of blowing up, right in the middle of the rear end was handy.

RE: Fuel Filler door

? Australia? My car has the flap on the right. The cars I help design have the flaps on the left. Ditto the UK.

And I can't believe NZ has any rule like that, as their compliance regs could be summarised "If the car is homologated in any of the following markets (long list) then it is legal here"


Greg Locock

RE: Fuel Filler door

I haven't independently verified this claim, but I heard it on a popular radio program, Klick and Klack, the tappett bros on NPR Saturday AM's in the USA (available on the web, and very entertaining) that the filler is always on the opposite side of the auto from the exhaust.

Now, my car happens to be dual exhaust, but they did not put the filler under the license plate as some cars I have owned it have had it located.

Is there any truth to that??  Surely Tom and Ray wouldn't put out bum dope would they??


RE: Fuel Filler door

I can't imagine that the left and right hand drive versions of the same car would have alternate fuel filler locations.

The argument about the exhaust sounds valid, as does drivers side for convenience, but then so does passenger side for safety if filling from a drum on the side of the road.

Several British homologated race versions in the 60's and 70's had twin tanks and filler. Mini Cooper and Cortina GT spring to mind.

pat   pprimmer@acay.com.au
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RE: Fuel Filler door

Just checked in the car park and all of them have the flap on the opposite side to the tailpipe, where possible.

I don't know if it is a rule, or just an outcome from the difficulties caused by packaging the tank and the mufflers.


Greg Locock

RE: Fuel Filler door


My intent was to point out that Humpty assumed that the drivers side always equals the left side.

RE: Fuel Filler door

Ah, OK. Anyway, we've definitely got some cars with the fillers on the left, and others on the right.

Some countries or states do specify tailpipe position to some extent (eg Viper is illegal in the UK due to the side exits, California specifies heights)


Greg Locock

RE: Fuel Filler door

One reason for the fuel filler door on the right is so that you can add fuel to the vehicle on the roadside and not be standing in a traffic lane.  If you notice, all German-made vehicles have the fuel filler door on the right.  Personally, I like the fuel filler door on the right because I don't have any problems opening the driver's door at a gas station (in the US, it is popular to have enormous concrete objects surrounding the gas pumps, which create impact hazards to car doors).



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RE: Fuel Filler door

Once upon a time, there was a theory that left hand drive cars should have the door on the right, right hand drive on the left. The idea was that a LHD car was more likely to be involved in an accident where the left side of the car was compromised. I don't think this idea had legs, but I think it persists as a cultural artifact.

As for locating it in the middle, do a search on "Pinto".

RE: Fuel Filler door

The Pinto filler was on the left side.  The root cause of the fireballs involved the diff housing acting like a can opener during collapse of the rear structure.

But all my single-exhaust cars have located the filler on the opposite side and my OE dual exhaust car put it right under the centrally-located license plate, so I also think that routing of the exhaust vs the filler pipe has something to do with it.  Maybe the side location of a filler indicates a fuel tank offset slightly toward that side as well, leaving more room for the exhaust on the other?


RE: Fuel Filler door

If there is a fuel tank one on side there is more room for exhaust on the other. Just like having the radiator overflow tank on one side and the windshield washer tank on the other.

I prefer my fuel filler on the passenger side (VW's in America) so I can open my door without problems. A co-worker thinks they should all be on the drivers side so everyone can drive to the right of the pump like driving on the right side of the road.

Here's a link to a thread full of car enthusiast's "wisdom" about fuel filler locations. Complete with a poll.


RE: Fuel Filler door

I was thinking that the "opposite the exhaust" argument would hold up, then I thought of my 84 Fiero... single exhaust, exiting on the left (drivers) side, filler also on the left.  Fuel tank is centrally mounted right down the spine. The later 6 cylinder cars had dual exhausts, but the filler remained on the left.

Aside from that one car, I can't think of another vehicle that has the filler co-located with the stock exhaust exit.  Two of my other vehicles, both LHD variants of originally RHD models, have fillers on opposite sides... both opposite the exhaust.

RE: Fuel Filler door

I think the "opposite to exhaust" argument still holds in spite of the Fiero--after all the Fiero was mid-engine, which presents all sorts of different packaging issues that most cars don't have.  Thus it would make sense for such a car to "break the rule", as the (presumed) design rule for front-engine cars wouldn't apply to it.

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