2nd Gas Tank

I have a 1993 Ranger XL 2.3L 5-SPD with 16.4 gallon tank. Is it possible to add a second tank and if so, how?

I dunno. Toss it in the bed and then siphon it out into the other tank when you need it.

I get around 40 miles out of an eighth of a tank.
Went about 20 miles with it on empty once.

there are bed tanks with pumps

It's a lot easier on an '85-88 ranger

How you'd go about doing it depends greatly on bed length.

On a Long bed you can easily install the fuel tank from a Bronco2
On a short bed that option won't work

what I did to add my "second"* fuel tank on my 1987 Supercab
was to use the PLASTIC fuel tank and skid plate from an F350-450
on homemade crossmembers.

as for fuel lines? I essentially made them by shortening the factory
fuel lines from the F450 tank donor.
using the selector valve from a 1988 ranger with factory dual tanks
adding a fuel door to the driver side bed skirt

wiring? Factory dual tank wiring (the entire frame harness) which
I had to modify because my selector valve was NOT mounted in
the factory location, because I'm NOT using a 1986-88 "main"
14.5gal fuel tank. My "main" fuel tank is a 21gallon tank from
a gen3 supercab)

My truck being a 1987 was already equipped with the dash wiring
for dual tanks so for me the wiring was literally a simple matter of
snaking a factory dual tank frame harness into place, after I extended
the wire for for my relocated selector valve.

I'm pretty sure that if I had to install fuel tanks on an '89-up
I'd probably use a scheme similar to that used on the 1991-up
F-150's which did NOT use a "selector valve" they used a shuttle
valve INSIDE the in tank unit where the pressure pump drives a
shuttle valve that opens a valve in the return fuel path.

1991-up F-150's simply switch the power to the in-tank
high pressure pump and using the pressure controlled return
valve to control where the return fuel goes.

LEt me point out something that might not be obvious,
The IMPORTANT part of any dual tank system is noot fuel being fed
to the engine, but rather control of the "Return fuel"

I can explain this in one word: "crossfeed"

If the return fuel is inadvertantly directed to a tank that is already
full it would be considered "Bad" though not in the ghostbusters
definition of the word, just below that...

If fuel isn't fed to the engine it won't run and if it isn't running the
computer will let the fuel pump relay drop out, you get 10-12 seconds
of run time MAX, if you are leaking return fuel?

Picture driving down the road spewing fuel....
I doubt I need to belabor the point....

* Now the reason I put quotes around the word "second" above
is because my "second" (see I did it again!) is actually my THIRD fuel tank.

I have in addition to my 22gallon (ok really 21.8gal, but I consistantly overfill it)
and my 19gallon "aux" tank I have a 40gallon tank mounted in the bed that is
disguised as a diamond plate tool box.
I say "disguised" because I cut up a diamond plate crossbed toolbox and
use the top (mounted with stainless steel piano hinge directly to the headgate)
and the back (which I haven't actually finished) to the bed deck and sides.

So my total fuel capacity is... (phrasing this with exquisite care)
just short of sufficient to do what I want to do.... which is to drive
unrefueled from my home in pennsylvania to my brother's Casper, Wyoming

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