Adding a Fuel tank for longer range

[BruceTS]

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Here's an option so you can double your range in a 3rd Gen 4Runner. In my case I will be removing my factory tank and will only run off this one. The Ford f150 91-96 rear tank will fit in between the frame rails and is rated at 18 gallons same as the stock one. Now if you really want to go crazy JC Whitney sells a 31 gallon replacement tank that is only 5" deeper. Eventually I just might buy one for those extended trips that I won't be doing any rockcrawling.

 

[toy_tek]

Interesting - thanks for posting. I was considering building a custom tank for that location but this would change things up a bit.

1. Looks like it fits above the bottom of the frame rails... true? Any room for a 1/4" skidplate? (I already have 1/4" plate material)

2. How is it plumbed? Any pics? How do you fill it?

3. What is the electrical schematic?

4. I assume the spare crane & crossmember needs to be removed?

5. Why are you removing your stock tank?

6. Any good places to source it?

7. Now how much does it cost to fill up? :ylsmoke:

 

[sami]

Nice! I was looking at doing this, and have been researching different tanks to use..

I'll keep the Ford in mind

Did you just put a checker auto fuel pump on it to transfer over to the main tank? Care to elaborate on the ins and outs?

Thanks

-Jason

 

[p1michaud]

Extending your range.

The Ford f150 91-96 rear tank will fit in between the frame rails and is rated at 18 gallons same as the stock one.

Excellent post.

More details please. eepwall:

Cheers,
P

 

[BruceTS]

This thread talks about the ford tank.
http://www.pirate4x4.com/forum/showthread.php?t=484247

As for wiring, you can rewire the ford pump and it will work, the sending unit will read backwards, so I wired the Toyota sending unit and added the lead for the low fuel light. Use fuel injection hose to extend the lines. The filler neck is in a more direct location than the factory tank and just have a tube of 2" pipe bent to fit. For my year model, the Ford tank has all the same lines; fuel, return and emission. Simply use fuel injection hose clamps to attach. The only difference is it doesn't have the filler vent line, but that isn't needed since it's a 2" tube vs 1". Because I'll be using the same size tank i'll still be Calif emission legal.

I'll post more picture when I get a chance showing the mounts, line routing and draw up a schematic of the electrical. Now if I were to keep both tanks, I'd wire the low fuel light in the main tank to a relay, switching the secondary pump on, transferring the fuel. For filling, I'd just add a "Y" to the filler neck so you can fill both tanks at the same time.

I will be adding a 11 guage skid plate to protect the tank, anything thicker is not necessary since it sits up so high and I rarely drag back there. As for getting rear ended, most cars will slide underneath, so I doubt the tank will ever get ruptured.

I have a 1.5" body lift so the end of the tank is just above the frame rail, but the end nearest to the tires is about 1" below.

Since so many F150's were built there should be no problem locating one at a salvage yard, mine came from a 95'

yes the spare tire crossmember needs to be removed....

 

[BruceTS]

Here's the new harness, I still may need to drop the tank to adjust the float, when I do I'll get a shot of the modified sending unit.


I cut the hardline going to the old tank, then attached some fuel 5/16" injection hose to extend the new tank. I used 1/4" hoses for the return and emissions....


Got some 2" to fabricate the fuel filler tube.



Now that I don't have the factory tank, it frees up the underside. Time to remove the crossmembers, clock the T-case and go flat belly......

 

[HOYTUSA]

The extra capacity would be great! as long you aren't sacrificing reliablity.

I went to the JCWhitney web site looking for the 31 gal but all I found were 38 gal tanks for the ford. I would not complain one bit if I was able to get over 700 miles between fill ups:Wow1:

this may require some more research

 

[BruceTS]

oops my bad it is 38 gallons not 31.....

Twice the capacity of original-equipment tank (38-gal. vs. 19-gal.)…twice the driving range. Replaces behind-rear-axle tank except on 1980-1989 pickups with dual exhaust which can also replace main tank. Heavy-duty steel is nickel/tin plated inside and out for complete rust resistance. Electrically welded seams are reinforced for greater strength…individually pressure tested for leaks. 34-1/2"W x 13-1/4"H x 26-1/2"L. Installs easily. Won't affect ground clearance, but spare tire must be relocated.
Includes: tank, lock ring, rubber "O" ring, spacers, bolts (to extend original-equipment straps), instructions and adapter kit (to modify and remount existing sending unit). Note: Fuel gauge will remain on "Full" longer because of increased tank depth. Not for diesel fuel.

 

[ttravis5446]

38 Gallons would be awesome, but man would hit hurt when it came time to fill it up. Gas was over $4.00 today and that was with a huge refinery 7 miles away.

 

[HOYTUSA]

anyone have any idea how much that tank would weigh full?

it would be a shock to the wallet to fill it up completely

 

[SAR_Squid79]

I have wanted to do this on my Tacoma for SOOOOOO long. I would do it like Scott did on the Expeditions West Tacoma (http://www.expeditionswest.com/equipment/tacoma/fuel_tank.html). I love how he had it setup as a true "Reserve" tank instead of just higher capacity. He set it up so that when he needed more fuel, he'd just pull over, and hit the switch, and transfer the fuel from the reserve tank into the main tank. The only exception is that I would want a more low-profile tank than Scott used. When I get back out to SoCal I'm going to try to find someone that can custom fab a tank for me.

 

[BruceTS]

At aprox 6 lbs. per gallon that would be 228 lbs and around $150.00 to fill....

now can you imagine having that tank + the stock tank.......... 56 gallon!

With my factory tank removed, I'm tossing around a few ideas on what to do with the new space. I really want to double triangulate 4-link first, this will eliminate the rear steer I currently experience when articulated. I'm even thinking about adding a storage compartment with under seat access for my recovery gear and tools.

 

[ntsqd]

Gasoline weighs 5.8-6.6 lbs to a gallon. I'm guessing that variance is mostly due to the percent of alcohol in the fuel.

While I've got that book out: No. 2 diesel weighs 6.7-7.4 lbs to a gallon.

(Alternative Fuels Guidebook, R. L. Bechtold; 1997, SAE; ISBN 0-7680-0052-1)

SAR: You might have better luck finding a tank builder where you are. CA is so litigious about things like that and combined with the scare that CARB has put into anyone remotely in the business of building such tanks I know that locally I'd had trouble finding anyone willing to make it. I know of one very busy shop that specialized in fuel tanks that closed due to the regulations and CARB's fear-mongering.
Best CA option would be to find a shop that builds custom tanks for boats.

 

[HOYTUSA]

I was doing some rough measurements on the 4runner and it looks like the 38 gal tank would hang down about as far as the stock spare currently does. It would need some protection for sure!

 

[xcmountain80]

I think depending on the application either separate fueler or auxiliary fueler, mine would be aux. I Like the idea of pulling over hitting the switch. Thoug why pull over keep on truckin. But then by adding said tank to spare tire spot it begs the question where does the spare go? On the rear? add up to $1200 for a swingout tire carrier. On the roof? I dunno about you but my last truck had the spare on the roof and what a pia to get it off. Inside the truck? Well my fridge lives inside and this would all but eat the remainder of my cargo space.



Aaron