Worst Car Inventions: Ford Uses a Gas Tank for a Trunk on Mustangs (and Falcons/Fairlanes)! 

LOL! As a teen in the 70’s, working on “old” 60’s cars, I loved the accessibility of the fuel tank & sending unit in Mustangs. Remember thinking, “I wish all cars were like this”.

In the early CJs, the gas tank was under the driver’s seat. Many pickups had the gas tank right behind the seat. We live and learn…thank you as always.

Steves's Mustang was Highland Green.

I sold my 2002 Jeep Grand Cherokee this past summer. It was equipped with the towing package with factory hitch and wiring. If so equipped, it had a metal plate between the factory hitch and gas tank. But many Jeeps were not equipped with the tow package and added an after-market hitch. These Jeeps had no plate to protect the tank from a rear end collision and an after-market hitch could penetrate the gas tank. So Chrysler sent out safety recalls on EVERY Jeep, even if equipped with the tow package. The incentive to bring in the Jeep was that Chrysler would mail out a $100 Visa gift card. I took mine in, nothing needed to be done, and still got a gift card. So fuel tank issues still exist.

The Pinto wagon was actually a great, useful small car for the time.

Nice to hear of someone else who prefers the look of the 1971 Mustangs to the prior models. The 1971 is drop dead gorgeous.

I had a 73 Gremlin with the Levi’s interior complete with copper buttons bought new off the lot as high school kid. The loan was for $63 per month, co-signed by a parent, paid for with $2/hour minimum wage job. This thing was a chick magnet, pretty much all any high school kid cared about then. As now. I still have the gas cap. My girlfriend drove a 72 Pinto, my mom a 74 Vega. The Gremlin was the best of these three by far. The Vega was a boat anchor.

Trunk engineering is an overlooked art. Case in point: the spare tire well of the '78-'87 GM G-body wagon is perfectly sized to hold a 15.5 gallon beer keg and 50 lbs of ice. Thoughtful engineers even included a drain hole which could be accessed by lifting a small rubber plug. I miss the '80s!

The AMC Gremlin was the best of the three... Thanks to Adam for another great watch of automotive history.

I was surprised to learn my 1962 Falcon had the gas tank for its trunk floor. Big fan of Bill Hickman’s work!

My dad was a ford man, he started working on cars in the early 60’s and me and my brother growing up we had a bunch of different shock tower ford’s. He always said to keep the rubber mat in the trunk and if you ever had to take a battery in one of those cars to put it on the floor behind the driver seat

Also, early pick-up trucks from the 60's into the 70's had the fuel tank in the cab behind the seat. You can tell which trucks had that design by the fuel fill door directly behind the driver's door.

A number of cars from the 1960s used this solution with a gas tank as a trunk floor. And newer had any issues.

I've owned many 1965/'66 Mustangs over the years. It was a never a problem or a concern for me. I never heard of a Mustang getting rear-ended and then exploding in flames. The 1968 "Bullitt" Mustang Fastback was Highland Green metallic.

It might seem strange but definitely worked, in later Falcons and Fairlanes the spare tyre sat in a recess in the top of the fuel tank. Ford used two bottom sections of the tanks joined together to make a 36 gallon long range tank. There was a Masonite floor board covered with a rubber mat to isolate boot (trunk) contents from the fuel tank in vehicles with the standard 16 gallon tank.

You did not mention that they did come with a rubber type trunk floor mat to prevent the battery instance you mentioned. Great content as usual Adam, please keep them coming and how about another look into that man cave of cars you have??????

I had two, a 66 Mustang and a 69 Cougar. The hose between the filler and the tank cracked on the Mustang. I scored a great deal on a Pinto Wagon when I sold the Cougar due to the Pinto fire issue, which didn't affect the wagons due to a different tank design. I guess the Ford design was better than VW, having the tank over your lap right by all of the electrical connections.

In Australia, a big adopter of the Falcon chassis, we used that fuel tank design until 79, when Ford Oz switched to one of the world's first plastic fuel tanks, suspended under the boot floor. However wagons still used the drop-in fuel tank idea all the way till their demise in 2008, albeit with a false plywood floor. My 82 wagon has this. I don't know about the US design, but ours had (on the large 80L versions), a recess for the spare tyre so that when you sat it in there, the spare tyre cover formed a relatively flat boot floor. Our 75 XB coupe had this type. I remember as a kid, an issue with the fuel vapour cannister caused the tank to pressurise and blow up like a balloon. My dad only found this out when filling up and noticed that it took 12 more litres than normal. He looked in the boot and noticed the boot floor has risen by a few inches. It actually split and a very dangerous attempt to braze it shut caused a small explosion in our front yard, freaking out our neighbours and of course my dad (who'd lost some of his eyebrows in the resulting fireball). That attempt wasn't entirely successfully either. That car always smelt like fuel whenever riding in until he completely replaced the tank. I must say though, the design was hardly a safety consideration amongst Falcon/Fairlane buyers, even after the more stringent crash standards came in through the years until the last wagon rolled out in 2008.

The French Connection has the best car chase ever. Bullitt and The Seven Ups were not too shabby either.

It looks to me that of course besides cost cutting being a reason for the tank to be the floor, I think that was an added bonus to the real reasons which was for better mounting, a larger tank & ground clearance because of the car's ride height being the actual situation they had to overcome, besides it's a lot more reliable than just two straps that would always rust out on cars very quickly in snow areas.

Don't forget that the 68-'72 GM pickups had the gas tank right behind the bench seat. I remember my dad telling me no one thought the wiser then, but when he restored his '72 he relocated the gas tank.

Lots of school buses had saddle tanks. The tanks protected the bus frames. How crazy was that.

Years ago, I ordered and installed a 3/16" thick, stamped-steel plate that fits over the tank / trunk floor of my 1968 Fastback. This essentially puts the tank on the outside of the car.

I learned about the gas tank as the trunk floor and the battery welding into it from Steve Magnate Of course they came with a vinyl or rubber mat as insulation

Yes Adam, the gas tank design that started on 1964 Ford compact cars like Mustangs , Falcons, and Pinto's was what they called a Drop-in Fuel Tank set up. There you have it.

The Ford Capri 69- 86 tank in boot Floor , The Vauxhall Viva ne magnum 72 -78 the same . No issues in Europe like the pinto bad press though . Maybe part of it was a European car was unlikely to be hit up the arse by a Ford Ltd !!! 😮😮😮 Great video as ever Adam 👍🇬🇧🇺🇸

In the 50's, 60's and 70's a lot of pickups, from all of the manfactures, had the fuel tank in the cab of the pickup. It was mounted behind the seat.

Funny thing you said about the battery in the trunk, I have a 65 Shelby GT350 with the battery in the trunk "right next to the gas tank."

There was a fantastic movie out called "Class Action" in the late '80s. Of course, it was a faulty blinker circut and the company was Argo Motors. It was really about Ford. Definitely one of the best movies of the time and still one of my favorites.

I pretty sure it was Highland Green, Steve's GT.

1970 Mavericks had the gas tank top as the trunk floor and since those were derivatives of the Falcon as was the Mustang.

I thought the Mustang gas tank trunk was a great idea. We could use that design these days to easily access the fuel pump for replacement.

I'm 60 years old. We drove a lot of used Falcons and Fairlanes when I was young and we never had a problem with the tank being there and no one ever blew up.

I much prefer the original Mustang to the way too heavy redesign.

Being a young owner of a 69 Mustang coupe that was normal to me, I didn't think anything of it until now. I also prefer the later Mustangs to the earlier and some of the 71-73s with their graphics and paint schemes were downright beautiful. The reason I owned a 69 coupe was because my dad couldn't quite afford to get a used 69-73 Mach 1 which is the only Mustang I really dreamed about and wanted.

I owned a very early '65 Mustang convertible that had a solid plate behind the rear seat. I understood all converts did for body strength.

My first two cars were Falcons. My second Falcon was upside down and end over end. No fire occurred. The chassis on those cars were built much stronger than modern cars that are made to absorb the energy of a collision.

Yes I had heard of this issue with the Pinto and early Mustangs. The early Mustang Fastback however does have a steel plate above the gas tank so it isn’t known to have this issue like the coupe does. Also there are kits that Mustang coupe owners can install to place a plate above the gas tank. This functions as a way to secure and stabilize the tank in the case of a rear end collision. Ford cleverly installed a piece of vinyl material in the trunks of the Mustangs to disguise the fact that the gas tank is your trunk.

My sister had a 1970 Maverick. Same set up in the trunk. When I saw that, I was appalled. She got rid of it not long after.

I remember that on my 70 Grande. Never really gave it a thought at the time. For all the reasons of the lack of safety in older cars that I love, I will look at them, but I won't own one or ride in one. BTW: at the time I hated the 71-73; however, I learned to appreciate them now.

Great idea for weight distribution. I remember the first time at Road Atlanta, (1977) seeing red boxes slung under the trunks and rear bumpers of GT and Production cars. I asked an older friend " What are those ATL boxes?" Fuel cell!

Plenty of Australian cars in late 1960s and 1970s had fuel tanks as boot (trunk) floor from at least Ford (Falcon) and GM known as Holden models like Torana. I actually dented one putting a heavy load in one, just reduced fuel capacity a bit. Easy to pull out the fuel tank or sender. I was a bit surprised when you suggested how rare in was in America.

My cousin had a 68 hdtp. He never knew that under the matt was the exposed tank. I don't know the full story but my uncle said that somehow he had tossed something heavy and apparently sharp into the trunk, gouging the top of the tank enough to where he could smell fuel, but couldn't tell where it was coming from. He took it to a shop and the mechanic knew right away. The tank had to be replaced. Once it was done, my cousin cut a piece of plywood to cover it.

I remember watching an episode of Dateline in the nineties about the Mustang drop in gas tank and Chev/GMC side saddle gas tanks. The show mentioned one teenager who died in a fire when his 65 Mustang was rear ended and another teenager who died in a fire when his 85 Chevy pickup truck was t-boned. They also mentioned the 60's pickup trucks with the gas tank behind the seat.

The GM truck side saddle tanks may have been "sub-optimal", but could be seen as an "improvement" over having the fuel tank right behind the seat INSIDE the cab. (I owned a 1967 Chevy P/U sometime in the 1980's). My brothers and I also owned a few rear engine VW Beatles over the years. They also had the fuel tank as part of the truck (in the front), and do not get me started about the VW Thing gasoline fueled heater.

One problem was when hit, the fuel filler tube would rip off the tank, exposing raw fuel to any source of ignition. I think this was more prevalent than the fuel tank hitting the rear axle.

I heard about this gas tank situation in about 1967. My cousin had a 65 Mustang convertible and had running issues. It turned out the roof leaked into the trunk and the water rusted the top of the tank into the gas. As far as the GM truck side saddle tanks. A news program tried to highlight the safety issue with video tests. They couldn't get a fire started and eventually got caught using explosives. Wind tunnel testing showed that a Pinto was more aerodynamic backwards.

The 1969 and ‘70 Mustang Boss 429 had factory trunk-mounted batteries. Also, Torinos/Montegos through 1971 had the same gas-tank-as-trunk-floor setup.

Of all of the subcompact’s the Gremlin was the best for being mechanically sound. It just didn’t get the best fuel mileage. 22 mpg was about average. But with a 21 gallon fuel tank you could go a long way between fill ups. The car was very simply built and easy to work on.

I own a 65 Mustang. I have never read any disparaging articles regarding problems with the gas tank being part of the trunk floor. I believe it was also part of the trunk design with the Falcon

I like the Gremlin. 😀

I remember around 1995-96 Lee Iacocca said in an interview "I wouldn't have said it if I knew to Goddamn office was bugged". He was in the oval office and talked about the gas tank problem with Nixon. Ford knew of the problem, but the bean counters advised it would be cheaper to pay the lawsuits instead of recalling the cars.

Bought a 1965 Mercury Comet in the 1990’s . Previous owner had put carpet in the trunk floor. Of course the trunk leaked enough to hold moisture on the fuel tank which was the floor. I promptly removed it exposing surface rust.Never saw fuel leakage but the Comet always had a slight gasoline odor when driving. Liked the car but traded it for a 1982 Ford Fairmont with the 200 six as well. Both cars were light blue four doors . The Fairmont/Zephyr was like an updated Falcon/comet for the time. Liked them both .

Adam, you're gonna hate this, but Ford continued this technique on the Falcon and its derivatives right through to the mid-eighties here in Australia. 😂

Don't throw shade on the Gremlin. My buddy and I beat the living crap out of one in the early eighties and it only stranded when it ran out of gas. That thing would run on 2 stroke fuel and never missed a beat!!!~~

Adam -- another great video. I remember Lee Iacocca being interviewed about this fuel tank-as-trunk-floor years ago, maybe on "60 minutes". His advice was "trade up". He further clarified that the average 1960's vehicle was nowhere near as safe as a new vehicle of the time (late 1990's; early 2000's) and should not be anyone's daily driver. He stated that these cars should be used for Sunday drives, etc., not in the thick of daily traffic. Very honest advice. Frankly, the safest of these older vehicles is surely your beloved 1960's and 1970's FoMoCo full-sized vehicles, where the fuel tank is vertical in the forward part of the trunk, where it is as far away as it can be from a serious rear-end impact. -Bobo KC

This is not any crazier than the fact that all of the big 3's pickup trucks as well as medium duty ones had the gas tank inside the cab behind the seat. Nobody back then thought it was odd. The GM sidesaddle tanks much better than that.

In my 1984 Renault, the gas tank was under the driver/passenger seat. (For better weight distribution.)

Soviet Moskvich cars had the same solution for the trunk floor) I guess it was somewhat a popular solution for the 60s)

The 1969 -1970 Boss 429 had a trunk mounted battery from the factory. I personally think it was a good idea to save weight and double as the trunk floor. We all had trunk mats back in the day, loved the ease of access to the sending unit, and I personally know of no one that ever had an issue with rust, fumes or fire with the design in the Mustangs.

I worked in detail at a Ford dealership in the early 70's and noted the fuel tank being the floor of the trunk in several Fords. I often wondered, how safe is that?

On my Falcon it was pretty dang sweet 60 years later when I wanted a fresh fuel tank and it took maybe 20 min. Good ole steel I'd still throw a jackstand in the trunk no worries

Truly amazing how long the Robert McNamara curse lingered on at Ford .

Interesting, your comment on preference of 2nd gen Mustangs, Adam. I’ve been a Mustang fan since I was a young kid in the 60’s. Always preferred first gen. But the 71-73 design has aged well. I’ve actually started looking for one to add to my fleet. However, it is one of those cars that really looks much better with a lot of tire. (Not the big rims like today). A set of slots or cragars, 15x10 rear and 15x8 front, just completes the car!

in the mid 1970s, I worked as an auto dismantler at a wrecking yard in while high school. So, I got to disassemble and learn about just about every car made from the late 50s through the early 70s. I remember the first time seeing the gas tank as a trunk floor and thought it was such a bad idea. Mustangs, Falcons, etc were cheaply built and designed cars. Mustangs had nice styling and very good marketing but, their design has turned me off from those cars ever since. The front suspension and steering is just as bad, then there are cheap things like - shock towers and the list goes on and on. Having loved GTOs and Pontiacs since I was 7, I learned just how much better the Pontiacs were built and designed by dismantling every brand from that era. I drive vintage Pontiacs to this day with well over 1 million miles on them. Mustangs are nice looking but, it ends there IMO

I have a 70 Mach 1. Beautiful car, but was amazed when I got it at how little protection that combo trunk floor/tank had...useless rear bumper, thin taillight panel, a trunk mat, and not much more. Also on the fastbacks, with the wide open sail panels and just a piece of vinyl covered cardboard to block the flames. The rear seat back is metal in this year but the flames could easily circumvent that up those sail panel chimneys. Package shelf no better. Was considering a fuel cell and a steel plate reinforcement instead of the original tank and sealing the sail panels, as was gonna track the car, but plans changed. Different times and priorities. People hate on Nader, but really there wasn't much corporate concern for consumer protection or safety prior...on anything, not just cars.

My dad’s ‘65 Land Cruiser had the gas tank under the passenger seat. Filler neck was exposed in the passenger compartment and had an inline rubber coupler between the neck and the tank. Needless to say, the old Land Crusher always smelled like gas, which was a constant joy for my mom. For her, the Mustang design would have been a great improvement. Hey, at least we had seat belts!

Alot of early pickup trucks had fuel tanks behind the rear seat ! My 68 C10 did ! Was nice in -°20 weather ! Never had a frozen fuel line !

Actually, I like this concept because, here in the Northeast, the top of the fuel tanks used to rust as there was no access to put some antirust between the car floor and the tank.

This sounds like someone trying to make up a problem that did not exist. How many MILLIONS of Mustangs were sold and I have never heard of a fire as a result of rear collision. It actually seems like a pretty good idea, making the tank easy to access as an old car to clean or replace the tank. I also don't see an issue with carrying a battery. There would be a rubber or tar paper barrier between the tank and the trunk floor. So let's see. Remove the mat so that the tank is bare. Now install a fully charged car battery so that when it does turn over it somehow turns COMPLETELY upside down and the posts make contact. It sounds like something that would never happen in a million years. I think you are stretching this one.

Dude, you didn't even mention, the "bolt" that was reason for the rear end crash vulnerability on the the Pinto in the 1st place !!!!

My 69 Toyota Corona mark two had the gas tank trunk floor with a spare tire sitting in the top of the tank

I never knew this, thanks for the video! The Mustang/Falcon wasn't the only one with something like this, though. The VW Beatle up to the mid-60's had its gas tank in the front trunk, secured to the car only at four corners, and the filler cap was also in the trunk, so owners had to open the trunk to fill the tank. In a crash the tank would be crushed, the gas cap would be forced off then gas would splash everywhere in the trunk. The trunk was separated from the passengers only by a piece of cardboard so it was bad news if a fire started (this was detailed in Ralph Nader's book on the Beatle's safety issues). Pick-up trunks commonly had the gas tank inside the cab behind the seat. When regulations forced them outside the cab, marketing departments suddenly bragged about all the storage space behind the seat. Then there's the Jeep gas tank under the driver's seat. Car design was different back then.

In the comic strip, Bloom County, a resident cockroach did song and dance tribute to Lee Iacocca: "Union busting, profit lusting, little Pintos all combusting, apple pie and Diet Coke-a, that's what is my Iacocca!"

6:10 Stainless steel was too expensive. This is probably either galvanized steel or terneplate steel.

The death of the Pinto was a direct result of the NHTSA requirement for 5 mph bumpers. The previous Pinto model years didn't have the issue of the fuel tank getting pushed forward. The early ones dropped downwards. There were only a few highly publicized incidents.

In a '55 Chevy pickup, the gas tank is literally behind the bench seat back The battery was under the floor.

Was the trunk fuel tank worse than the pickup trucks’ in the cab fuel tanks?

The design was called a "DROP IN" fuel tank. The news vulture program "60 Minutes" did a hit piece on May 17, 1999 detailing the issue for car owners. Mustangs and Pintos were joked about by my high school crew in the late 70s for being exploding death machines. Unfortunately we had an acquaintance lost in that type of accident in the early 80s. An aside, VW Beetles had an issue called Ejector Seats, where the passenger seat would shear off the guide rails in rear end collisions. The Ralph Nader Syndrome was everywhere with these investigative journalism stories starting in the 70s.

Didn't know about the fuel tank floor doubling as top of gas tank. Uh, to me, it seems an incredibly stupid and dangerous place to save a few dollars, especially at the cost of safety. I'm speechless.

The petrol tank being the boot floor was standard practice by countless car makers in the 60s. What counts in a rear end collision are the box sections surrounding it, a mere sheet metal skin above the tank wouldn't change a thing. Also, not mounting the fuel filler pipe in the centre of the tail panel does help. Note that e.g. Chevies built in Denmark don't have them, they have a fuel filler door in the right quarter panel, and the old Mercedeses that had them behind the rear number plate had a substantial rubber gaiter between the pipe and the tank to allow for severe deformation upon impact without undue consequences. Also, if a spark from a boot mounted battery can possibly ignite petrol fumes, there already is something severely wrong with the tank. Much worse than the fuel tank acting as the boot floor is the practice to just put it in the boot, but weirdly nobody has an issue with that.

Our Aussie Falcons in the 60’s had the fuel tank as the boot floor, and the spare sat in a wheel shaped recess on top of the tank. My 1968 Falcons was my first car, I thought this was pretty normal at that time, maybe not so much though!

It's called mechanical engineer'd multi tasking. Saved Ford $1.07 per vehicle . Give that ma a raise.

I read somewhere that Mustang convertibles had an additional problem of the doors jamming shut when rearended. You're potentially trapped in a car with the passenger compartment full of gas from the ruptured tank.

I had purchased a used 75 Mustang fastback back in my early 20's and was told about the exploding gas tank. I don't if that was true for that model Mustang but I didn't care. I had some really sweet times that car. it was a dark olive green with a beige interior and a automatic. Great memories!!

Yet those millions of first generation Mustangs never developed a reputation for blowing up, the way that the Pintos did.

Up until 1973 pickup trucks had the gas tanks in the cab. When you filled up the tank you smelled gad inside and you could hear the gas sloshing around when you turned corners.

My Pinto was great! I like the prototype better though I did not know of that design in the 1970s. From the Hatchback Pinto I went to a Toyota SR5 to an AMC SX4 Eagle and an GMC Jimmy. All great vehicles that provided exceptional service.

Finally thank you I have been saying that exact same thing for years Ford was notorious for their gas tank issues, I don't know the igniting seemed to be more prevalent in the smaller Pinto, than the bigger cars, A friend of mine inherited a 67 or 68 Mustang fastback and when restoring it he would say in puzzlement my cars cargo area bottom is the top of the gas tank so I always though it's the size of the car issue

In the mid 80s i had a friend w a 67 comet, cousin to the falcon fairlane platform. The gas tank flange held it in place to the rest of the floor w sheetmetal screws. I ribbed my friend about it some as i had the opposite in engineering w my 65 buick. Lots of bracing thicker metal and generally a similar overall intermediate size but with more horsepower and torque. He preceeded to hop up the 289 and broke stock clutch, driveshaft and differentiall. Was a 4speed non power steering stripper that was beautifully simple to wrench on but rode like a jeep with the airshocks in back. Practical 6 passenger size in basic mustang falcon platform.😮

We had a Falcons, Corvairs, Mustangs, Pintos and didn't get rear ended. Many cars had fuel filler at the rear. Our family's 73 Monte Carlo had filler under license plate with rubber hose. No air bags or cameras either! We lived. Looking at today's people who can't drive or think, Darwin Theory shows safety equipment is a waste.

I remember looking into the rear compartment of my father's Skoda S100, wondering I could see the road under the vehicle. I was a child in the early 80s, and the Skoda had the engine in the back.

Ironically, the Pinto's gas tank was mounted underneath the trunk floor, isolatating it from the trunk and passenger compartment. This design desicion was praised in an article I read published at the time of the Pinto's launch, although I can't remember which one. Australian Ford Falcons of the 60s-70s also had trunk floor tanks. The top of which had a large indentation for the spare wheel. The design was changed for the 1979 XD series Falcon.

The first Pinto's used 3 attachment bolts for the bumper. The problem was the center bolt pierced the tank in a rear end collision. They quickly went to 4 bolts. As far as 'the study', standard management over active brown nosing.

I have 1967 Volvo 122S that's set up the same way. Makes it easy to replace the fuel tank, just remove the carpet, remove some sheet metal screws and lift it out. Though you do have to go under the car to disconnect the fuel line.

Never knew that. Thanks for the video. Mustangs were made at the River Rouge complex I think. You could do a whole series of videos on that amazing place. Piles of raw materials that came in on Great Lakes ore ships on one end, finished cars out the other end. I guess Henry Ford's suppliers were mine operators. Maybe he owned them too, don't know.

My grandmother's top of the line 73 Ford Maverick had the fuel tank that served as the floor of the trunk. It also had the nororious Firestone 500 first generation radial tires. We always kidded her it was a bomb ready to go off. It was trustworthy car though and she drove it for over a decade. I do think the domestic manufacturers discounted the repetitional risks to these cost cutting designs.

I prefer the fighter jet style, where you're just surrounded and protected by the fuel tanks lol.

My Volvo P1800 also uses the gas tank for the trunk floor. Surprising considering Volvos safety reputation. The p1800 predates the mustang, maybe that’s where the idea originated from.

I had a 1969 Falcon 2dr. My gas tank sprung a leak. Being the trunk floor made it quite easy to replace it (with a salvage yard find).