Need A More Accurate Fuel Gauge With 60 Gal S & B Fuel Tank

[MAtkinson]

I'm putting a 60 gallon S & B replacement tank in my 06 3500 Quad Cab Long Bed. S & B allows the use of the factory pump and sender. But there's problem because the original sender float travel is less than the height of the new 60 gallon tank. So they tell me it's only accurate at the mid point (1/2 Tank). Therefore it registers "Empty" long before it is and you don't get the full benefit of this tank. Does anyone know of a sender with longer travel compatible with the factory fuel gauge? (Or any other solution?) I recognize this is a long slender tank subject uphill/downhill angles that can starve the pump.

 

[Randomrunner12]

following because I want to do this tank upgrade in the future as well.

 

[AH64ID]

It should work similar to the 55 gallon setup I put in my ‘18. Once I learned the differences I had no issues putting 47-51 gallons into the tank during a fill up.

Due to the tank height it stays full for about 10 gallons, but then it moves like it did with the stock tank. It was actually pretty accurate at that point, aside from DTE.

The empty reading being higher is because the volume of fuel at say 1” depth is probably double the OEM tank, but the sender still reads the shallow depth.

AFAIK there isn’t anything you can really do differently, thou I do think the tank manufacturers should supply new float arms with their tanks. They can’t be that hard to mass produce.

Maybe you could make your own longer float arm?

I do suggest taking notes on how much fuel it takes to fill it at certain levels, 1/4, 1/2, red markings, low fuel light, etc. That’s useful in planning your stops to maximize fuel.

 

[bcbender]

I assume your FP module is like the one below, I would think that it should read to empty since the float is / will lay flat on the tank floor (unless some feature in the tank bucket prevents this)... If not, I would not hesitate to modify or make a new wireform (float arm) to replace the OEM wireform and increase the swing arc of the float,.. should not be too hard but dont have one here to look at. Perhaps one could simply bend the end to allow the float a full range arc. Either way it appears it should measure to empty.

[ EDIT: I was not considering the change in the scale... As Sag2 says, just confirm it is on the bottom of the tank and it'll be good. ]

 

[AH64ID]

I assume your FP module is like the one below, I would think that it should read to empty since the float is / will lay flat on the tank floor (unless some feature in the tank bucket prevents this)... If not, I would not hesitate to modify or make a new wireform (float arm) to replace the OEM wireform and increase the swing arc of the float,.. should not be too hard but dont have one here to look at. Perhaps one could simply bend the 90deg angle to less (45deg?) to allow the float a full range arc. Either way it appears it should measure to empty.
View attachment 139405

Yes it should work normal to empty, with the only difference being the added volume at a specific depth.

When the low light came on in the ‘18 with the 55 gallon tank I recall having around 7 gallons left and would plan my stop based on the economy I was getting.

I would not change the bend on the arm, as that will negatively impact readings. The only mod I would do is a longer arm to compensate for the added depth of the tank.

 

[Yo Hoot]

Doesn't answer the question but think about commercial airliners. They have many tanks of many shapes for maximum fuel load. They use capacitive senders that are a tube within a tube. They program the readout based on the level taking into account the shape changes as the level drops. Capacitive fuel level senders are available but not worth the trouble fitting one and it's associated support hardware.

 

[BarryG]

yo hoot
I actually put a capacitance sender in my 01. I had no problems with mine at all and as far as I know it is still working fine (I sold the truck to my BIL in 2017).
I did a write up on it. Again I had no problems but I did not mess with any of the calibrations. I took it out of the box and installed it and it did fine. At least a few others who tried it ran into some problems. I have no idea why they had problems as mine worked fine but nonetheless they did.

this thread explains what I did back then and some issues that a couple had
https://www.turbodieselregister.com/threads/fuel-sender-capacitance-type-install-notes.199933/page-2

If someone was going to try this route now I know you would want to verify the ohm range of whatever year truck you are working on as the ohm range I used was correct for the 01 model year but no idea if it was/is the same for all years, don't know if the 3rd gens and now 4th gens or even the first gens are the same. I do know that for the 01 model year and range I used was not the same as other makes of trucks. Whether it would even work in a 3rd and especially the 4th gens no idea as the computers have evolved over time. I would think a third gen might be fine.

To the Op I put a 55 gallon tank in my 17 using the stock sender and it worked fine. Yes I could drive about 200 miles before it came off the full mark, after that the gauge reading was pretty good, the low fuel light would come on though I don't recall how much fuel was left in the tank but one time it came on and I immediately filled it up to get an idea and the same thing with when it hit "E" I just don't remember what those numbers were now. I filled it up at various points 3/4. 1/2, 1/4, low fuel light on and at E to get an idea of what represented how many gallons left just so I would have a good idea. None of which really mattered as I just filled up the same way I always did usually between 1/2 and a 1/4 usually closer to the 1/4 knowing I still had plenty of miles to find a fuel station even out in the sticks. The DTE was definitely not correct and on the 17 there was no way to fix it at least at the time.

 

[sag2]

Bending the float arm down would make the low end read more accurately. Obviously the upper end would stay on full for a much longer time. Pretty good trade off in my book, and it's free. Just have to mess around a bit to get it to drop on the bottom when the sender was at empty. Knowing the lower end is much better than a few hundred miles before it comes off full.
Trying to change the length of the are may not work depending on the orientation of the sender in the tank.

 

[MAtkinson]

Thanks for the advice. I had already concluded the lengthen the arm but perhaps there were alternatives?? (I can't be alone in this.) I will do some measuring & experimentation before installation to determine a correct arm length. Above Full isn't so important BUT Empty is very important. I figure I need a reserve and enough the handle tilt/angle. I will utilize an AirDog Pump/Filter System with Vulcan Suction/Return. It will take some time but I'll report the results. I appreciate the ideas & comments. Thank You...

 

[AH64ID]

I don’t think empty will be as big of a deal as you think.

Which Vulcan setup are you looking at?

How much power are you planning to make? If it’s under 600 rwhp there are better filter options with a stock LP than the aftermarket external pump. The stock LP is one of the most reliable setups, if it supports your power needs.

 

[MAtkinson]

Since writing the above this morning I "chatted" with Titan (Remember I'm using an S & B tank) They claim no problem because they use the OEM Sender just like S & B and it's correct at 1/2. I pointed out the lost available capacity because the gauge registers "E" yet 10-12 gallons remain out of sight & out of mind...? (That's what.., 150 miles of range?) So a 60 tank only has an effective capacity of 48-52 gallons? The Titan guy came to admit I was correct and confessed "they have discussed supplying a longer float arm". So there you have it. (Remember I had the same discussion with S & B.)

I've designed and built several diesel tanks for Class 4-6 trucks. I designed and built a 145 gallon tank that sits inside the frame and above the axles of a gooseneck trailer. It has it's own three-point rubber suspension and Vee Bottom Profile so I can run it dry. The truck can pull directly from that tank. 145 in the trailer plus 165 (3 Truck Tanks all connected) = 310 Gallons or 3000 mile minimum range. All by turning two valves (drivers side floorboard) using two fuel gauges. It's made many, many cross country trips hauling machinery - non-stop with two drivers. This 06 will replace that truck with the same fuel capacity, better mileage and higher speeds. The old 79 GMC with a 4-53T Detroit Diesel and Allison Automatic + Gearvenders will be stripped to the frame for a total rebuild & major upgrades. (435,000 Miles.) OLD GMC's NEVER DIE THEY JUST GO FASTER..!

Thanks again for helpful suggestions. I'll keep you informed.

 

[MAtkinson]

So far I plan to use the Vulcan plumbing to draw through the OEM pump assembly. I'll connect through valves to the AirDog FP-100 Pump/Filter assembly then off to the engine. There will be a 100 gallon bed tank when needed (Plumbed-In) and connections to the trailer tank. I don't anticipate more than 450-500 HP using a Banks Econo-Mind Control and basic airflow & exhaust upgrades. As long as we can make 70-75 loaded (30-35K Lbs Max) and 80-85 empty we're happy. I need simplicity, extreme reliability, enough power, good mileage, lo--ng range (and a rare burst 95-105 to get out of trouble would be nice...)

 

[Topzide]

@MAtkinson, Do you have fuel stickers or do you buy fuel in each state that you travel through? I thought that when you have DOT #'s and are for hire, you either had to have fuel stickers for the states you pass through or were required to purchase enough fuel in each state to make it through. Just know somebody that got caught without fuel stickers for the state he was passing through and cost a lot more than if he had receipts or stickers! Be careful on the trips and stay safe out there! May want to add 1/4" plus plate to the doors as an upgrade with the road rage going on out there!

 

[CVR222NV]

Since writing the above this morning I "chatted" with Titan (Remember I'm using an S & B tank) They claim no problem because they use the OEM Sender just like S & B and it's correct at 1/2. I pointed out the lost available capacity because the gauge registers "E" yet 10-12 gallons remain out of sight & out of mind...? (That's what.., 150 miles of range?) So a 60 tank only has an effective capacity of 48-52 gallons? The Titan guy came to admit I was correct and confessed "they have discussed supplying a longer float arm". So there you have it. (Remember I had the same discussion with S & B.)

I have the 60 gallon Titan tank in the same truck you have and you are correct based on my experience. Takes a while to come off empty and when I get to empty and fill up I still have a reasonable reserve. I use my trip odometer to track mileage per tank to determine my range. I have been getting a minimum of 600 miles per tank (combination of highway/offroad/ towing) but have got to 800 miles per tank (empty/highway). I run around in some petty remote country so when the fuel gauge starts getting to empty I start planning a run to town to fuel up. That said, the extended range over the OEM tank has been a substantial improvement.

 

[MAtkinson]

FYI: We are not For Hire. We haul our own machinery. Always totally cover up the load and "Look Like" we are well under 26,000 (for what times we are well over). Make about 1-2-3 runs a month that usually includes a weekend. Our machinery is sophisticated, expensive and needs a smooth, safe ride. Carry our own "Paperwork" to verify the load and ownership. Use "Ag Plates". "Generally" do not stop for Weight Stations (Ag Exempt). They think the fuel lines to the trailer are air lines for air brakes. Keep a Low Profile. Only been Chased 3-4 times on 43 years and left them so confused that nothing happened.

 

[AH64ID]

So far I plan to use the Vulcan plumbing to draw through the OEM pump assembly. I'll connect through valves to the AirDog FP-100 Pump/Filter assembly then off to the engine. There will be a 100 gallon bed tank when needed (Plumbed-In) and connections to the trailer tank. I don't anticipate more than 450-500 HP using a Banks Econo-Mind Control and basic airflow & exhaust upgrades. As long as we can make 70-75 loaded (30-35K Lbs Max) and 80-85 empty we're happy. I need simplicity, extreme reliability, enough power, good mileage, lo--ng range (and a rare burst 95-105 to get out of trouble would be nice...)

For towing that heavy I would suggest you keep the rwhp around 425 max, that will not over tax your oiling and cooling systems.

You also don't need to do any modifications to the fuel system for that level of power, but added filters are a good idea. The in-tank pump has proven to be more reliable than the aftermarket external pumps, and has plenty of flow to push thru multiple filters and supply ~450rwhp+.

Banks isn't the best route to go on these trucks. A Smarty Jr is a good choice, the S06 would be a little better, but a full custom MM3 tune would be the best bet for heavy towing. The Banks is also +100 rwhp, which won't put you in the 450-500 range, but closer to 400.

The only think I would do to the intake is a home depot CAI. The exhaust is good to well over 600 rwhp, and is nice an quiet at 4". I would add an exhaust brake if you don't have one.

 

[MAtkinson]

Good thoughts. If I stay with the stock pump I can't deal with the other 2 fuel tanks (100 Gallon Bed Tank + 145 Gallon Trailer Tank) unless I ran two parallel fuel systems with some valving and controls into and through a common filter system then to the engine pump. I do keep noticing comments the OEM Tank Pump is more reliable than the aftermarket pumps. Seems odd...? Those FASS & Air Dog Systems "look" so much more substantial and reliable. Thanks for the advice and please keep the ideas coming.

 

[AH64ID]

Good thoughts. If I stay with the stock pump I can't deal with the other 2 fuel tanks (100 Gallon Bed Tank + 145 Gallon Trailer Tank) unless I ran two parallel fuel systems with some valving and controls into and through a common filter system then to the engine pump. I do keep noticing comments the OEM Tank Pump is more reliable than the aftermarket pumps. Seems odd...? Those FASS & Air Dog Systems "look" so much more substantial and reliable. Thanks for the advice and please keep the ideas coming.

Why not have the aux tanks dump/transfer into the trucks tank? Thats how most aux tanks are setup.

 

[bcbender]

I have the 60G tank in bed, here is the writeup I did for dealing with plumbing it into the OEM tank, I put the AN bulkhead fitting in and L-Track so I could take the tank in / out when I need or want the extra bed space. You could do a Y valve and run both tanks gravity into the OEM tank. For me 90+ gallons gives me all day towing ( > 1000 mi) and free to find the best price diesel.

https://www.turbodieselregister.com/threads/aux-tank-install-on-2020.270812/page-2

 

[User113]

following because I want to do this tank upgrade in the future as well.

Runner: If you find a tank that fits the '04s, please post. I would like to increase my tank, but I can't find a replacement for our model year.