Many years ago, I was at a gas station behind an 80’s Jaguar and noticed that this car had the gas filler cap on BOTH sides of the car, It makes me wonder why the no other manufacturer has thought of this? What rationale do manufacturers use for the location of the gas cap?
The side that has the tailpipe . . . the filler neck is usually on the OTHER side
I’m talking about cars with single exhaust
Tom and Ray talked about this on the show 
You have to realize that the placement of two gas tanks and two gas caps on those older Jags was a compromise, based on the difficulty of placing one decent-sized tank within the structure of those cars. What you might be perceiving as an advantage was actually a problematic situation, as driving more than a moderate distance required filling both tanks on those Jags.
Or, were you under the mistaken impression that these older Jags had one gas tank with two gas fillers?
I’d say that Jag had 2 gas tanks…just a guess…
Just for arguement’s sake, let’s say that a car has one tank. Why not 2 filler necks, one on each fender?
Too expensive, especially for the minor advantage gained. Automobile manufacturers sweat pennies, and this addition would add more than $100 I would guess. No way.
This would cost more, add weight to the car (thus reducing fuel economy), and probably even reduce safety a tiny bit (as I’d imagine it’s safer to get hit on the side without the filler tube). This doesn’t seem worthwhile to me.
The way all of the gas pumps are oriented proximity-wise where I live, I can’t see any advantage. A bit more cost, a bit more weight, double the possibility of a (admittedly highly unlikely with today’s caps) EVAC leak, and no advantage.
But I have to admit… it would be worth it to have some of the old classics I’ve dreamed about, 
For the record, I test drove and considered buying a '70s Jag. But good sense took over just in time. Them there old Lucifer (Lucas) electronical systems were a test of one’s tolerance.
Remembering flipping down the license plate to filler up!
My 1979 Chevy pickup has the two tank’s fillers on both sides of the truck.
But THESE days . . ( grrrr ) the gas stations are rarely built with these vehicles in mind. Unles you plan ahead ( when you own one , you do ) you find the hose won’t nearly reach, or doesn’t .
AND . .
This narrow frame design was subject to recall where . . they could never actually FIX anything concerning the vulnerability of the tanks outside the frame rails so their best stab at a solution was to give you a $3000.00 voucher to buy a new truck.
LOL, didn’t the '56 Chevy have the gas cap under the tail light housing?
Wondering how my 72 ford f150 with the gas tank behind the front bench seats would fare these days.
@smokie Yes, those Jags had 2 tanks, one in each fender.
Did any of these vehicles with two tanks and two filler necks have a “balance hose” between them?
Specifically one that would enable both tanks to get filled from one filler neck.
I disagree. The car in question, say a mid-80’s XJ Series, had a single gas tank. Not in the fenders, but in the trunk behind the rear seatback. It was a long tank that ran the width of the car, and as such it was quite easy for it to have 2 short filler necks on either side. That way the driver didn’t need to worry about which side of the gas pumps to pull up to.
^
The Jags didn’t have any interconnection between the tanks.
There was a switch on the dashboard to switch from one tank to the other, and–of course–there were two gas gauges. When you consider that the electrics for this equipment were probably made by Lucas, it’s a wonder that more Jags didn’t burn up.
“didn’t the '56 Chevy have the gas cap under the tail light housing?”
Actually, all of the '56 GM products had hidden gas fillers.
That was GM’s big engineering advance for 1956.
You wouldn’t need 2 filler caps if every manufacturer added a little arrow on the fuel gauge, like Ford does, pointing to the side that has the filler! Best, zero-cost convenience item added to any car IMHO. Great for rental cars and multi-car families. My wife has to remind me her car’s filler door is on the right, not the left like my cars.
That cute little arrow on the fuel gauge that indicates which side the fill is on . . means NOTHING to the 99% who never bother to read an owner’s manual.
I told my wife about that last year about her own 06 Escape hybrid . . not a clue !
’‘oh ? So that’s what that means.’’
I thought most brands of vehicles have had an arrow indicating the gas filler side for some time now.
That cute little arrow on the fuel gauge that indicates which side the fill is on . . means NOTHING to the 99% who never bother to read an owner's manual
You wouldn’t have to read an owners manual to make the connection between a little arrow on the gas gauge pointing left or right… No insult intended to your wife, Ken, but what did she think it meant?