So I decided with the horrible gas mileage 351m's are famous for, I wanted a 38 gallon tank for more range. I figured I'd share some tips and tricks I learned during my install. I have a '79 F100, 2wd, auto. This is the only dent I've ever owned, but I think the rear/behind the axle gas tanks are all the same ... I think.

These are the extensions for the mounts for the gas tank. They came with the tank, but looked like cheap zinc plated pipe from homedepot. I sprayed then with rattle can bed liner for some rust preventative, and anything painted black looks cooler!

This is my modified fuel pickup. I used a pipe cutter to make a cleaner cut. The tank also came with a copper pipe to extend the pickup. I used a small propane torch to solder it together because my soldering gun wasn't putting out enough heat. I used some 10 gauge wire I already had laying around as well. I used what seems like too much wire, but I wasn't sure if my soldering job was gonna be air tight so I left enough room to slide everything apart without having to cut the wire. I know I'm missing the filter/sock on the end of the pickup



Next I wire wheeled the tank braces and sprayed them with the same bed liner I used on the pipe extensions. Important note: read the directions before using something like this. After I sprayed them, I read it takes 72 hours to cure (Hence why I finished on a Wednesday and not a Sunday.)


Here's a shot of the front after it was mounted. Tip #1, even if your bed is removed like mine is, the tank must go in from the bottom! Dont waste 10 minutes like i did. Also, I must have put those dang bolts on 10 times because I kept doing this in the wrong order. I highly recommend loosely putting the top braces on first then raising the tank and putting on the bottom braces. Tighten the top braces first then the bottom braces. Tip #2, have a helper. As good as my 3yo's intentions were, he wasn't of much help, but I still enjoyed the wrenching time with him.

Another note, I forgot to take pictures but I used one of my kids popped bike tire tubes in between the braces and the tank. There was a lot of moving around so I used some headliner adhesive I had to help hold the rubber in place. I had to stop here because a bad thunder storm rolled in quick. I'm gonna put the pickup in and run new lines tomorrow after work and give an update then. How this helps someone. Keep wrenching and keep 'em on the road!

 

This is very interesting to me as I am considering the same mod for my '76 F-100 RWD LWB.
So where did you source the tank and sending unit/fuel pickup? I know that Dorman makes a 38 gallon tank but does not offer a matched sending unit/fuel pickup. It would be very helpful to know of a source where these key components are matched.

 

I was keeping an eye on them from the shopping tab on google. I found this one from am-autoparts on eBay. They were selling it for 98.91 with no tax or shopping cost! It didn't come with a sending unit, just the copper pipe to extend your stock one. But it did come with a new lock ring and gasket for the sending unit.

 

Spectra makes a 38 gallon tank, and I have seen people install them in 92-96 trucks. Not sure how different the frame rail widths are between these years

 

Did you locate a pick up tube end filter sock?

Tank drop 101 https://www.ford-trucks.com/forums/1...l#post14696841

 

One thing not mentioned in the thread - when you are removing/replacing the gas pickup use a dowel or block of wood to tighten the lock ring - sparks by gas tanks can be a major (albeit very quick) problem.
Also - do a trial fit of the pickup, then use a flashlight at the gas filler port to make sure the pickup is correctly aligned in the tank- its tip should be in the little square depression in the bottom of the tank.
The sending unit is made for a 19 gallon tank, and as shown it will probably read empty for about 20 gallons. If you double the length of the float arm and adjust to fit the tank, if like mine you will run on F for 7-8 gallons, 1/2 tank at about 18-20 gallons used, show E at about 32 gallons used, and have a 5-6 gallon reserve. While wrestling that big tank into the frame rails (you will find it a little too big to raise directly into place, you have to tilt it, I think so if the retaining bolts come out the frame will help keep it from falling out) that jack with a piece of wood on it will come in real handy.

 

That is why you use a brass punch & hammer.
Dave ----

 

IMO there is no fire risk, you use a flat tip to unbend the tab and then it like a quick tap to unlock the lock ring. It's not like I am running a 7" grinder cutting the tank in half.

 

So this is the f26e like I'm buying for my obs...guess I'll order 2...

 

I got mine from lmc truck, but haven't taken the truck out of storage yet to tackle this

 

I finally got the pickup in place and ran the rubber fuel line. The original hard line is a b***h to get out from around the steering box and motor mount. I hadn't run fuel through the hard line in probably a year and when I used my angle grinder with a cutoff wheel to remove it, gas leaked out! I immediately turned the grinder off and got out from under the truck. I placed a towel under the leak and blew into the line from both ends to empty it. After that hour and a half ordeal was over I moved on to the fuel pickup. Absolutely test fit the pickup and check placement, both location and depth. I did this by bending the copper tube and using a flashlight in the filler hole. Amateur tip of the day, don't let your flashlight fall in the gas tank. I also bent the float arm to keep it from touching the bottom of the tank. It's not perfect but with an empty tank my gauge read just above empty. And with 3 gallons of gas in the tank it's halfway between empty and quarter. Tip from my retired mechanic neighbor: I put some extra fuel line I had on the "in" side of the pump and ran it under the bumper into a gas can and let the truck run for one to three minutes. I then attached the fuel line from the tank to the "in" side of the pump and started the truck again. This way I didn't have to kill the battery or the starter trying to get fuel into the carburetor. Another tip from the same neighbor was to use a screwdriver on the solenoid to start the truck instead of getting in and out of the cab every 5 minutes. Once I had a steady flow through the fuel filter I knew I was done. And at this time of night I'm too lazy to sort through all the pictures but here all the new ones. Enjoy.

 

As far as I can tell they sell 38 Gallon bronco tanks for 92 to 97 but not the 91 f250 dual tank I have? (Links?) Has anybody tried this?

They changed the type of innards in the tank 92. My rear tank currently isn't working, may as well go bigger and better while fixing.

Thanks

 

I used to consider a 38 gallon tank, but back in the '80s when I built my hitch receiver, I think I built it up too close under the stock 19 gallon tank, so I never went there. I have a little over 4 inches between the hitch and tank bottom. Would have been nice at times in the '80s / '90s, but I don't see a need now as I'm not apt to go so far between gas / pee / coffee.

 

I dont think anyone makes a 38 gallon tank for any pickup truck you have to get the one for the Bronco and fit it into your truck.
Now part of the problem is in 87 the gauges / senders read backwards from what the <86 trucks do and why you cant use the 87> senders.
The other "got you" is when they started using in tank fuel pumps, EFI and some 80's 460's, the opening went larger.
Then again if you can get a <86 low PSI in tank pump / sending unit you can wire it in and do away with the motor driven pump, it would help on vapor locks
Just something to keep in mind if going to do this swap.
Dave ----

 

The tank is made by Spectre of Canada I think. Available from Rustys Bronco graveyard I beleive along with an extended pickup.