How many gallons?
 

My gas gauge doesn't work and I have to keep up with the odometer to know when to stop for fuel. I lost track of the mileage last week and stopped at the Shell station. I was stunned to watch it consume 18 GALLONS!!!! First off, I must have been only a few yards from running out of gas, and second, I thought the tanks behind the seat was only supposed to hold 16 gallons? What's the capacity supposed to be?

Dave

Approximately 21 gallons, actually. Nobody knows for sure; I have once put in 21 and a very little bit of change beyond!

You had plenty of time left ;)

21? really? I can usually only get 14 gallons in mine, and that is when the guage is kissing the E

I have put more than 20 gallons into mine... your gauge may be off a bit.

Some trucks had smaller tanks, every one I have ownerd held about 20.
I drove into the gas station once and fillied it with 21.75 gallons.

The owner's manual lists two tanks (at least in 1970) IIRC. a 19 gallon and a 21 gallon. You should have one of the two. Don't know how you tell the difference, I think the bigger (c/20+) trucks were supposed to get the extra 2 gallons capacity. No idea why have two different tanks...

That's interesting, my 70 owners manual (which came in my first longhorn built in 4/70) on page 88, it says 10 - 30 series has a 20.0 gallon fuel tank standard...that same tank is 16.75 metric gallons though.

In my 69 GMC owners manual, it sway 1500 - 3500 back of seat tanks are Approximatly 22 US gallons.

Ever think fuel pumps at the stations might not be 100% accurate or calibrated???

I'm sure they're not always dead-on. But you gotta love how even GM said "Approximately 22 Gallons".

The fuel pumps at gas stations are required by law to be calibrated. That's what those stickers on the pumps are for, they get regular inspections to test accuracy. Some stations tried to reprogram the electronic ones to overcharge you on anything but 5 or 10 gallons (where the tests were usually conducted to) but many states got wise and started varying the testing size and those responsible faced tough criminal charges.

in my 67 owners manual it says standard in c10-c30 models is 18.5 and optional is 20.5

"Required by law" and "actually dead on every single day" are two different things. ;) Insurance is required by law in so many places...yet how many people get tagged by uninsured motorists?

Interesting thing though, even the factory listing from GM says they are all 21 gallon tanks.

All the tanks I have seen were 21 gallon. Butttt, depending on the truck, some empty a lot quicker then others@#$%^&*( hehehehe

The 72 restoration guide shows the C 10 -20 gal
C 20 -21 gal

:flag: :bowtie: :canada:

Keep it full and carry a '' hillbilly credit card ''.......... a can and hose!!! LOL!!!!!

From my 68 manual.

Hmmm, 20 gallons.
I wonder if this is what they all are and ppl have been reading it incorrectly.

You are right and a good example is in our area where weights and measures admits they are undermaned to the point that any given pump is only checked probably once every 3 or 4 years , regardless of what the seals say .

Call 1-800-222-1020

This is for the Restoration package, which has the specs.

Have your vin number ready when you call, it's a free package with quite a bit of information.

Just called to get one on my 77 Blazer and had it in less than a week.