Move the gas tank or no?

[Accelo]

Here is a picture of what I ended up with after a long drawn out deliberation.
It's a reversed Blazer fill. Fills like stock, no burping required and it's easily accessible for filling.
Picture was taken before it was screwed down and painted to match.

[indymachinist]

Yeah, fuel tank in the cab was safe all the way to 72.

Also, 7 out of 10 doctors prefer marlboro cigarettes , lead water pipes are safe, knob and tube wiring isn’t dangerous, mercury is ok to play with in your bare hand, asbestos is a perfecty safe and useful product… etc etc

[Steeveedee]

Originally Posted by Accelo

Just for clarification;
The Pinto's tanks were in the back but also on the inside with the occupants.

The problem with Pintos was that installing the clamp for the filler tube wasn't easy due to the angle that the tool had to be used, so the line workers rotated the clamp for easier installation. In a rear-ender, that clamp screw would puncture the tank, causing a fuel leak. QA should have caught that. The clamp and screw were positioned that way for a reason- to avoid fuel tank punctures in a crash. The movie "Top Secret" notwithstanding, Pintos didn't actually explode when rear-ended.

I worked for three Chevrolet dealers in the early '70s. Another problem that I remember was when there was a recall on Buick Opels. The windshields would pop out when the vehicle rear-ended another one. Turns out that the assembly line workers were greasing the windshield seals instead of installing them according to the instructions.

[67 twins]

Originally Posted by indymachinist

Yeah, fuel tank in the cab was safe all the way to 72.

Also, 7 out of 10 doctors prefer marlboro cigarettes , lead water pipes are safe, knob and tube wiring isn’t dangerous, mercury is ok to play with in your bare hand, asbestos is a perfecty safe and useful product… etc etc

Just remember it was the squarebodies that were involved in a class action lawsuit regarding fuel tanks. YMMV

[jeffahart]

Originally Posted by indymachinist

Yeah, fuel tank in the cab was safe all the way to 72.

Also, 7 out of 10 doctors prefer marlboro cigarettes , lead water pipes are safe, knob and tube wiring isn’t dangerous, mercury is ok to play with in your bare hand, asbestos is a perfecty safe and useful product… etc etc

Install some air bags in your truck... be safe... please!

j

[1970cstblazer]

Originally Posted by 67 twins

Just remember it was the squarebodies that were involved in a class action lawsuit regarding fuel tanks. YMMV

I'd much rather have the tank inside the cab than those side saddle bombs on the '73-up. That was the most idiotic placement of a fuel tank. Lets protect the fuel tank with a weak piece of sheetmetal, and make sure to sandwich it with the frame rail...

[leftybass209]

About the tanks and explosions.

Have you ever seen an explosion and thought, if i were only 6-8 feet from that explosion i'd be safe?

The kill radius of a grenade is 10-20 meters. I can guarantee after throwing a few that you won't feel safe at 21-35 meters. Point being, if you drive a gasoline powered vehicle, you're firmly and securely INSIDE the kill radius of the tank exploding, regardless of where you put the tank.

[1970cstblazer]

Good point on the radius. It would theoretically take a much greater impact to have a puncture and possible subsequent explosion with the in cab tank. The weakest most vulnerable part of them is the neck getting ripped off.

[Accelo]

I was in a VW that caught fire. It had a full fuel tank.
It just leaked out and burned, like any other fire.
It was exciting, as I hurt my knee when I bailed over the guard rail.
The fire department showed up 20 min later. Nothing left but no explosion either.

Sometimes the gas tank will rupture and the gasoline will ignite. That gives a pretty good fireball but it really isn't an explosion. The gas tank won't explode like a propane tank because it is designed to rupture before dangerous pressure builds up inside. Bear in mind that under normal circumstances the pressure in the gas tank is basically atmospheric. The only way to make a car explode like you see in the movies is to put a bomb in it.

The idea is to not have this fireball in the interior.

Now we can move on to EV batteries and the fires they cause\.

[dmjlambert]

Well darn it, if I can't go up in a big satisfying explosion like in the movies using stock parts, I'll have to look for some aftermarket explosives to sandwich between the tank and seat back...

[chevmn]

For nearly 20 years I was a volunteer firefighter, and fought many vehicle fires, and I never witnessed even one vehicle actually explode. Several leaking fuel lines, and a few punctured tanks (none were in cab tanks that I can recall, most were cars with rear fuel tanks). One of the most memorable was a pontiac which flipped over at high speed, and caught fire in the middle of a highway upside down. After it was extinguished the tank had swelled up to about twice it's original size, but again...no explosion. While many believe vehicle fuel tank explosions are common, I have yet to see one, and believe they are probably rare. YMMV.

[Joyridin]

Originally Posted by JNiemela

Ok. I've got a 68 CST with a 396. The gas tank is in the cabin and I've been deliberating on moving it to the bed. I don't want to use a filler in the bed and would want to add a door and filler to the side of the bed. But my mechanic that has done a few of these said just to get a new tank and lines and leave it. The current tank vents gas fumes when it's full and is the original tank.

What do you guys think?

I moved mine because it added a bit more room with the aftermarket seats, and I wanted to put speakers in the cab corners. It added a lot of storage space between the seats also, which in these cabs, is really nice to have. Absolutely nothing about safety came to mind. I put the tank filler behind the tail light. Works great with no issues at all.

[Hawkynz]

Leave it. Unless you are building a show truck or autocross style, it's not worth it. I have built an autocross truck from the ground up and relocated the tank because it was the trendy thing do. The original location is fine. It's extremely easy to work on and parts are cheap. Also, you do not have to fab up a system to fill the tank unless you just cut a hole in the bed, but why would you want to do that. I suggest fixing the fume issue and driving the heck out of it.

[1967GMCC20]

Yeah, tank under back near exhaust is right up there with the 71 Pinto I owned.

I'm good with carburetor, and having tank above fuel pump is more efficient, why they start so dam good.

[yote1234]

I Like STOCK, restore the hoses and seals

[indymachinist]

Originally Posted by jeffahart

Install some air bags in your truck... be safe... please!

j

I probably will in the rear coils!

[Extended Power]

I moved the tank outta the cab for a few reasons:
-room for speakers/subwoofer. (I’m 54 and still like it loud)
-no stinky fuel smell.
-more weight to help lower the rear a bit more. (With a full tank)
-better weight transfer for racing.
-better traction, for racing.
-makes room for different seat options.
-running an in-tank fuel pump, you can’t hear them at all.

[mxerhale]

I'm totally onboard with Extended Power, moved it for traction and an attempt at chassis balance. It wasn't too expensive using a Tanks Inc. universal tank and I cut a door in the bed floor sheet metal with a Dremel. I have heard nothing but compliments on how nice the truck rides and I believe moving the weight back really helped that.

[Casper42]

I've never had any "venting fumes" into cab issues, or concerns on my three C/K's - if you are there's something else going on.

[Richard]

Waking up hanging upside down by my lap belt after being knocked out cold, with gas dripping in the cab was all the reason I need to move it and add three point belts. Not building a 100 point stock resto show truck, I am building a truck that will be my main daily driver.

Edit- See some talking about explosions. A fireman saying they are uncommon. If would have died in an explosion that would be better than being burned alive with the accelerant leaking in the cab. Some have pointed out things are done differently with time. There is a reason for that. If you choose to ignore, that is your choice.

[jeffahart]

Originally Posted by Richard

A fireman saying they are uncommon. If would have died in an explosion that would be better than being burned alive with the accelerant leaking in the cab. Some have pointed out things are done differently with time. There is a reason for that. If you choose to ignore, that is your choice.

And the truth is... you're way more likely to die with your engine sitting on your lap in an intersection. If that fireman is an old guy, like me, and was around when back in the 60s/70s he'll tell you that. Most dangerous thing in your truck is the engine sitting in that frame(unless you have a 4x4). If you smack into something head on, you can adjust the dwell angel while waiting for said firemen! But hey, you have to be comfortable with your setup. But you know, if gasoline leaks from your fuel tank, no matter where it's located, and ignites... you're getting a hot foot either way. That said, I did consider moving my tank at one point, I wanted the space behind the seat.

j

[Casper42]

Originally Posted by Richard

Edit- See some talking about explosions. A fireman saying they are uncommon.

Uncommon is actually non-existent. I've seen many automobile fires. The gasoline simply "fuels" the fire, as if one putting lighter fluid on a camp fire. There are "pops" and such, but far, far from anything like what one sees in television.

[chevmn]

Originally Posted by Casper42

Uncommon is actually non-existent. I've seen many automobile fires. The gasoline simply "fuels" the fire, as if one putting lighter fluid on a camp fire. There are "pops" and such, but far, far from anything like what one sees in television.

Well put. We put out a lot of automobile fires with a small dry chemical extinguisher. The normal process was remove oxygen or fuel and the fire will go out. The dry chemical removes the oxygen (usually), then simply deal with the fuel leak as best you can. Sometimes if you simply could not remove the source of fuel, it meant flush the fuel away with water until it is all diluted or washed away (sorry, that is how it was done). Keep in mind this was 40-50 years ago. But, not all vehicle fires involve fuel at all, but the stuff you see on tv and movies where they explode with a few minutes is pretty much non-existent. But, as others say, location of fuel tank is personal preference, if you prefer in back between frame rails I would go that way. Too much to modify to no beneifit to me. But, nothing wrong with either.

BTW, probably the worst fire I witnessed involving a vehicle was the result of a mechanic working on the plumbing to dual tanks on a mid 70s square body truck. He was using a trouble light (the old style with a bulb), and raw fuel hit the hot light bulb, which exploded, igniting the fuel. Those working in the shop were unable to extinguish the fire in a timely manner, and the dealership was a total loss, along with several vehicles in the shop, and new cars in the showroom.

[MikeB]

I don't remember smelling gas in the cab during 34 years of driving my 69 C10. However, I have smelled gas fumes in the garage due to the vented filler cap. But it only seems to happen after a drive. Gotta come up with a solution to that some day.

As for the tank behind the seat, I think it was a bad idea. But probably not as bad as a Pinto tank near the rear bumper!

[silverstreak]

I'm on the fence with this myself. The "project" I recently bought already has one mounted under the bed but has the filler in the floor which will be a pain to fill as you have to stretch over the bed side or tailgate to reach it. I'm also concerned with water getting into the tank from rain or melting snow. At this point I'm considering going back stock with everything new. The gas tanks on my motorcycles are pretty much in my lap. I try to be a careful driver, but you can't drive for the other person.