Auxilary fuel tank

[HenryJ]

Wonder if this would work on a crew cab?

Auxiliary Fuel Tank System

I'm thinking come up inside the bed with the fill. Looks like there would be room now that my spare is mounted on the rack.
It would be nice to lower the weight of the fuel and free up the toolbox for gear.
Heck I could even use both auxilary tanks for a fuel capacity of 57 gallons. That would put me around the 1000 mile range
That is almost 350 lbs of fuel though. Not really what you want to pack all the time.

[Blaze One]

that would definetly free up space , but hopefully it would not affect you clearance angles .

[BADs Crew]

Here's one for the S-10 first Gen that may work.

Dual Gas Tanks (Blazer fuel tank between rear frame rails)

[killian96ss]

Heck I could even use both auxilary tanks for a fuel capacity of 57 gallons. That would put me around the 1000 mile range

You could drive all the way to NY and only have to fill up 2 times on the way!

Steve

[HenryJ]

Looks like it just might work-



Having removed my spare from underneath ,after going to larger tires, I now had unused space underneath.
With a little measuring it looks like the Isuzu tank idea may work for my truck. I picked up a tank, pump, filler neck and shield from a 1989 Isuzu Trooper for $50. My fourth try on brackets and second type of tank looks like it just might work. I tried a 1997 Isuzu Rodeo tank first, but the vent tube interfered with a crossmember.
Hopefully I will get the chance to do some more work on the install this weekend.

There are a few photos at the bottom of this page - 20 gallon auxillary fuel tank

[SONOMA915]

If you find some brakets that work, could you please post them also?

[Pauleo]

Hey Brule. Wouldn't that tank be a bit dangerous if you had someone rear end you???

[HenryJ]

If you find some brakets that work, could you please post them also?

I wish you could "just find" some brackets. I am custom fabricating them.

Wouldn't that tank be a bit dangerous if you had someone rear end you???

I don't think so. I have the hitch there and it is no worse , and perhaps better than the same tank mounted in the Trooper, Rodeo, and Amigo.
There are many vehicles with rear mounted tanks, and even though a few had problems, it was primarily the tank design that failed more than the location, IMO.

I haven't heard of any Isuzu tank failures.

[F9K9]

You might wanna nickname your faithful steed "Pinto"

[HenryJ]

Hung and plumbed today.
Wiring tomorrow.

This is not one you guys want to try. Way too much work.

[malkavian]

holy cow.... I havent read this thread I thought it might be the original thread on the aux tank in your tool box. I have to admit HJ you never cease to admaze me. Have you been able to tell if it will affect your departure angle. One more question are you going to make a skid plate for it.

[HenryJ]

If you draw a straight line from the bumper to the bottom of the tire it is well within that angle. It is also higher than the axle tubes. It is bound to affect departure somewhat though. If nothing else it is 132 lbs of fuel behind the rear axle.
It came with a shield, although I have not yet mounted it. I am going to change the mounting brackets and make sure that it will support the weight of the vehicle.

[HenryJ]

Well I managed to wire the fuel pump today. It turns out that I had already prewired the other momentary switch on the rear wiper / washer switch. All I needed to do was add a relay and run the wire to the back. It hums , so I assume that it will work. I did go back and add a LED indicator light so I know it is getting power to the relay.

None of the gauges that I had around are going to work So It looks like I will replace the digital clock with a digital fuel gauge. I ordered one from Summit and install it when it arrives. The gauge says it can be calibrated to work with virtually any sender. Lets hope so, I have had a hard time finding anything that operates from 16 to 120 ohms.

The install would not be so bad if it were not for the tight fit. The brackets lap over the top of the frame and come down between the spring shackles and the tank to the side mounting points on the middle lip. The frame is 35" between rails. 34" between the spring shackle bolts and the tank is 33" wide at the mounting lip. This doesn't leave much room.

I tucked it up as tight to the spare tire crossmember as possible, leaving about 1/2" space. Four 3/8" bolts hold the top of the bracket to the frame, and six 5/15" bolts attach the brackets to the tank. The brackets are not rectangular, since the tank needed to be offset slightly forward to clear the hitch.

I opted to bring the filler neck up inside the bed. I used an Isuzu Trooper filler neck with a first gen S-10 mounting cup. I had to tweak the vent tube to align it with the tank and to clear the frame. I drilled a 4 1/4" hole through the bedliner and bed in the right rear corner. Primed the edges and added trim around the edge. The cup bolts up from the bottom using the stock hardware. The filler tube mounting flange was trimmed and drilled to mount to the S-10 mounting cup. and about a 6" long filler hose with a 45 degree angle attaches it to the tank.
Now some will say , "Why in the bottom of the bed?" Well the way I use my truck I should work just fine. I didn't really want to punch a hole in the quarter panel unless I add a factory gas door. Who knows that may happen someday? The bed is easily repairable if need be.

The plan is to wait for the fuel gauge before filling with fuel. That way if I need to make any changes , I do not have to deal with a full tank of fuel. On a side note, this tank does have a drain plug, NICE! Should the need to recover fuel arise , that will make it easy.

One of the worst parts of the install is tapping the vapor recovery system to tie the systems together. I pulled the charcoal canister and cut a tee into the line about an inch from the canister connection.

Adding the fuel line was easy. I just uncapped the unused connection on the fuel tank selector valve that was added for the first auxiliary tank. This tank is mounted below the top of the stock fuel tank , so siphoning should not be an issue.

Now I await the new gauge, and to empty the other auxiliary tank. Then take out a small loan to fill up

[F9K9]

..........Now I await the new gauge, and to empty the other auxiliary tank. Then take out a small loan to fill up

Nice description, HJ

I can see fll-ups breakiing the $125.00 mark

[HenryJ]

...I can see fll-ups breaking the $125.00 mark

You hit that nail almost exactly on the head!
I still had just over 1/2 tank left on the stock tank. I filled up everything for a total just over $125.

The rear tank took 21.43 gallons to fill with out "topping off".

I don't care for the side mounted fuel gauge sender. It actually leaked a little and I had to sung it up. I did have it out several times while trying to make a fuel gauge work and they were a little on the loose side. Still a top mounted sender would have less chances to leak.

For now I will pack both tanks. At least until I am confident that the new system works well. I may even leave them both in for the winter. The added weight on the rear could be an asset.

[SONOMA915]

How about a picture of those brackets and maybe the completed install????

[HenryJ]

It will be a while before I complete the install with the skid plate. I want to make sure everything works right first.
Here is a picture of a bracket -



I added several others to the mod page as well.

20 gallon auxillary fuel tanks

[HenryJ]

Just over two years now and I finally get around to installing the auxiliary fuel tank shield.



It only took a couple hours to cut off the stock brackets and fab some to bolt it up. I don't know why I had put it off this long.



I guess the incentive to have things ready for Utah next year helps quite a bit. One less thing on the list.

[killian96ss]

With all that gas you should be able to do the entire trip without refueling.

If anything "you" might become the closest gas station and make some new friends in the process.

Steve

[HenryJ]

My range is just over 800 miles if I run the main tank low. I don't like to do that. Usually I fill up around 750 miles. That is 40-45 gallons depending upon the driving I have been doing.
I go a month between fueling on day to day driving. It is nice to pick and choose when to fuel. No worries about jumping in the truck and going. I can make a days worth of driving without stopping for fuel.
One of the best things I did to my truck for sure!

[F9K9]

I am sure that you researched it and may have even posted but, why does a Blazer's tank not work? I can't interpret technical info that is provided by sites like GM Upfitter.com to understand it. BTW, it might be worthy to download and save since, it will likely be lost soon, Brule. You are high speed now and no excuses.

[HenryJ]

I am sure that you researched it and may have even posted but, why does a Blazer's tank not work?

It can. This is the link in the third post of this thread The PuddleSkipper's Dual Gas Tank Mod.
I like my tank better for the ease of installation.

I can't interpret technical info that is provided by sites like GM Upfitter.com to understand it. BTW, it might be worthy to download and save since, it will likely be lost soon, Brule. You are high speed now and no excuses.

I see lots of legalese and very little information. Not sure if there is a value to retaining it?

[F9K9]

............I see lots of legalese and very little information. Not sure if there is a value to retaining it?

You're probably correct but, it was a little proof of my fight with corporate GM customer service over their Z trim height specifications.

A pretty depressing thought now, that I look back at it. It was just a thought that the frame specs may help.

[HenryJ]

... It was just a thought that the frame specs may help.

Good thought. The specs are in the service manual too.