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HI All, Lets talk about this tank and Sump issue question.. First your Stage I Lift Pump Operates at a 50-70 psi push to the Stage II filter under the hood, The Lift Pump is about 2 feet from the Suction pickup tube which is inside the Fuel Sending unit Sump... That pick up tube is inside the sump with a screen and has a 6 inch cylindrical shroud around it that has 2 red rubber flapper One Way at its valves at the base of the Canister where Fuel is contained and Sucked by the Lift pump..
So as long as you have been driving around slushing fuel for stop and go and rock and roll, about a Quart or more of Fuel is always inside that Canister until you Run the Tank Dry or Near Dry...
Thus putting a Sump in the Tank is Waste of money and time.. the Stage I lift pump is Dumb,, all it does is Suck and Blow or better word Push Fuel to the Stage II Filter.. at a 50-80 psi rate as for Volume Flow I have not tested that,, but I would say this,, at least 1-2 gallons a minute static.. when the CP4.2 High Pressure Pump is Sucking for fuel from the Stage II filter the flow rate is even higher. But remember your not really using that amount of fuel at any time.. you would be doing a lot to be using a pint of fuel in a minute.. rest of the fuel is being return to the tank..
Look at the pictures.. of the Fuel Tank Sending unit as it is called that serves the Lift Pump
So Unless someone is near empty and they park the truck on a steep Front End Down Positon or a Steep Front End Up positon there will be fuel in that sump for the Lift Pump.. However If your That Low on Fuel what can happen is the Lift Pump is Sucking to Fast to suck the sump area dry for a moment until some fuel can get back in the sump and your Sucking Air which can Cause "Low Pressure Warning" and that message is coming from the Stage II Filter Canister where it Monitors the Pressure of the Lift Pump Only.
Here's a good understanding info on the Fuel system and look at the Pics I have attached..
http://www.nissantechnicianinfo.mobi/htmlversions/2015_October_November_Issue_4/Fuel_System.html
See pics below as well..
Enjoy Merry Christmas to All
 

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For a stock tank it works as designed. We are talking about making a aftermarket tank with known issues work. Because obviously if you take time to read any of these threads the stock set up is not working with this tank and people are not being able to utilize the extra gallon's out of this tank. So yes the sump is a great idea because gravity works and will continue to work. Not to mention if someone is tuned and has larger injectors blah blah blah they can take advantage of the larger outlet than the factory draw straw to use larger fuel lines.
 

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DTF, makes sense.. thanks for sharing.. here's one..
Just for fun, let's say your XD stock cruising at 60 mph averages at fuel burn rate of 20 mpg. Then it would burn 3 gallons of diesel in 60 miles, or 3 gal=12qts x 32 oz in a qt = 384 oz burned in 60 minutes / divide that by 60 =/ min in oz. = 6.4 oz of fuel burned per minute / divide that by 60 sec. in a minute = 0.1066 oz. per second or 3 grams of fuel per second..
Pulling a load average with Xd average is 14mpg , 60 miles burn at 60 mph = 4.1 gal =524.8 oz /60 miles = 8.747 oz / min or 0.14 oz per second = 4 grams per second..
By the numbers... something to think about when your driving down the road
A jigger of liquor 1.5 oz = 42.5 grams.. as humans we have a high burn rate poor mpg.. actually if you do 3 or more of those most likely you will be late for supper.. lol :)

Merry Christmas DTF
 

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It's a shame that the mfg offers a subpar product at an extravagant price. When I buy new I don't expect to drop more cash to correct a faulty designed product, and won't. There are other options to get the job done. If not and it's needed, then I'll make it or have it made as long as the cost is less than or equal to the sub par poorly designed product.
I have the tank and have had many phone calls with Titan tank about this problem. I took several videos with my phone showing I had no problems starting the truck with 2-3 gallons in the OEM tank and no issues starting. Switched to the Titan tank and have issues starting once the needle gets into the red on the fuel gauge. I explained this to them and they assure me their tank is "fine" and exactly the same as the OEM (distance wise). I just refuse to drill a large hole in a $1,200 dollar tank to fix this issue. So far, even though the tank has it flaws, I still feel it was well worth the money especially pulling a travel trailer.
 

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I have the tank and have had many phone calls with Titan tank about this problem. I took several videos with my phone showing I had no problems starting the truck with 2-3 gallons in the OEM tank and no issues starting. Switched to the Titan tank and have issues starting once the needle gets into the red on the fuel gauge. I explained this to them and they assure me their tank is "fine" and exactly the same as the OEM (distance wise). I just refuse to drill a large hole in a $1,200 dollar tank to fix this issue. So far, even though the tank has it flaws, I still feel it was well worth the money especially pulling a travel trailer.

Are the tanks that set inside the bed just as bad or more expensive and not worth the extra cost? Sounds like the aftermarket tank mfg doesn't care to remedy the issue.



I get the reasoning that it's a necessity to have a larger tank when traveling long distance when pulling or not. And the after market tank issue is not a big deal simply because it's a necessary item, so one either carries a full five gallon tank and/or refills at 1/4 tank. That's what most people I know do to stay away from being stranded with no fuel.
 

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For a stock tank it works as designed. We are talking about making a aftermarket tank with known issues work. Because obviously if you take time to read any of these threads the stock set up is not working with this tank and people are not being able to utilize the extra gallon's out of this tank. So yes the sump is a great idea because gravity works and will continue to work. Not to mention if someone is tuned and has larger injectors blah blah blah they can take advantage of the larger outlet than the factory draw straw to use larger fuel lines.
I've read all the threads and discussion on this tank and guess I'm a little confused. If the overall tank height of the aftermarket tank is no more than .25 inches difference from the factory tank in height then I'm not understanding what the percieved problem is everyone is talking about with pump starvation. The variance of .25 inches in height of a tank is not going to have that much of an impact IMO.
 

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For a stock tank it works as designed. We are talking about making a aftermarket tank with known issues work. Because obviously if you take time to read any of these threads the stock set up is not working with this tank and people are not being able to utilize the extra gallon's out of this tank. So yes the sump is a great idea because gravity works and will continue to work. Not to mention if someone is tuned and has larger injectors blah blah blah they can take advantage of the larger outlet than the factory draw straw to use larger fuel lines.
I've read all the threads and discussion on this tank and guess I'm a little confused. If the overall tank height of the aftermarket tank is no more than .25 inches difference from the factory tank in height then I'm not understanding what the percieved problem is everyone is talking about with pump starvation. The variance of .25 inches in height of a tank is not going to have that much of an impact IMO.
It's not the height. It's the surface area of the bottom. Let me speak metric for a minute because SAE units are stupid

If you have a square container that is 10cm on a side, then the surface area of the bottom is 100 sqcm, so 100 cc of fluid will fill the container to a height of 1cm.

If you make the container 20cm long instead of 10, then the surface area of the bottom is now 200sqcm and the same 100 cc of fluid will only fill the container to a height of 0.5cm.

If we assume our 50gallon aftermarket tank is about twice as large as the OE tank in surface area, a given volume of fuel will only fill it to about half the height as the OE tank.

So, even if the starvation height is the same, the volume left in the tank when that happens is higher.
 

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As anyone considered the Hydra matte from Holly or extending the pick up tube toward the cab. To me it looks like the time you would run into trouble is blow a quarter of a tank and point teen downhill all everything would run towards the cab
 

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Discussion Starter · #30 ·
For a stock tank it works as designed. We are talking about making a aftermarket tank with known issues work. Because obviously if you take time to read any of these threads the stock set up is not working with this tank and people are not being able to utilize the extra gallon's out of this tank. So yes the sump is a great idea because gravity works and will continue to work. Not to mention if someone is tuned and has larger injectors blah blah blah they can take advantage of the larger outlet than the factory draw straw to use larger fuel lines.
I've read all the threads and discussion on this tank and guess I'm a little confused. If the overall tank height of the aftermarket tank is no more than .25 inches difference from the factory tank in height then I'm not understanding what the percieved problem is everyone is talking about with pump starvation. The variance of .25 inches in height of a tank is not going to have that much of an impact IMO.
Agreed, the diff is in the oem tank you’ll have say 1.5gals of fuel remaining where in this LONGER tank at the same tank level there will be around 3.5 gals remaining making it seem like you don’t get to use it to its full potential.

It isn’t a flaw in design but a limitation for how to get a larger fuel tank in my view.

The bean sump just allows you to use every bit of fuel in the tank vs the stock setup which no matter the tank will be hard to use every last drop of fuel but then again in a diesel I also believe you should never run it close to empty so I wouldn’t wait for it to get in the red either way.
 

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Speaking of fuel and tanks,, here's something for those of us who are stock with the Diesel XD. Was doing a fuel gauge accuracy test after replacing the fuel sending unit.. I put 12 gal in for a totally dry tank.. gauge read 1/16 of inch about 1/2 tank.. Ok no problem, now drive until the Warning "Low Fuel Came On.. Did so just to the Right of 1/8 tank Red Zone.. At that point Combination Meter gave Warning and stated 90 miles till empty.. I reset the Trip meter to compare when she is empty.. Note.. Carry a 5 gal can of Diesel in Bed so if I'm in the middle of No Place I can get started again.. I continue to drive and by this time the Trip Meter is at 40 miles driven and the Combination Meter Now Reads ------ No miles left.. reminder initally it stated 90 miles to aprox empty,trip meter now reads 40.. So I have not traveled 50 miles when she reads ----, and the Fuel Gauge is Now Buried in the E zone past the red to the right.. No Problem
I have driven home and now parked.. Next morning go out to Start Truck,, Will not start because I can hear the Stage I Lift pump Cravitation trying to Suck fuel it can't get.. because the Fuel Sending Unit Canister where it draws from has overnight let the fuel that is in its basket leak back to the tank..
Resolved, simply put the spare 5 gal in, did the 2-4 cycle prime method for the fuel system.. Start engine.. All Good..
I have shared this for a few reason..
1. I wanted to find where the real Empty Low fuel Won't start condition existed. for my truck after 50 of driving, and shut down if left sitting for say an hour or so.. your not able to start my truck because the fuel that was in the Fuel Sending Canister bled back into the tank and now Not Enough Fuel in Tank to fill the Canister for the Pickup Tube to Prime the System.. Note: when your this low and you do not put fuel in, and you keep trying to prime your just adding more Air into your Fuel System.. also if you add enough air you can cause a situation where it will never start until you crack injector lines.. Been there done that with these XD's so when Nissan the system is designed to Purge the Air,, this is true, With a Limit to how much Air you pump in and where it get's trapped.. If in the Rails,, you will have to crack injector lines.. to purge..
2. When your that low on fuel and your running it will keep going because your only pulling about (.10 oz or 2.83 grams) of fuel rate when driving 60 mph based on 20mgh average.. Thus is why you can keep goinq until you suck her dry, But
3. But and there is always a Butt,,LOL Once you Shut down.. even after You put fuel in say shortly later after sitting you make suck some air into the system and have to prime or find a delay of engine start..
4. Bottom Line With the XD - Don't Run it Down Past deep in the Red Zone.. Get Some Fuel when She says Low on Fuel, will save you some aggravation especially you don't have a Spare 5 Gal of Diesel laying around handy..
See Pics to better understand the above and your sump Fuel Sending Unit

Enjoy
Merry Christmas and A Great New Year!
 

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Premium Member
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For a stock tank it works as designed. We are talking about making a aftermarket tank with known issues work. Because obviously if you take time to read any of these threads the stock set up is not working with this tank and people are not being able to utilize the extra gallon's out of this tank. So yes the sump is a great idea because gravity works and will continue to work. Not to mention if someone is tuned and has larger injectors blah blah blah they can take advantage of the larger outlet than the factory draw straw to use larger fuel lines.
I've read all the threads and discussion on this tank and guess I'm a little confused. If the overall tank height of the aftermarket tank is no more than .25 inches difference from the factory tank in height then I'm not understanding what the percieved problem is everyone is talking about with pump starvation. The variance of .25 inches in height of a tank is not going to have that much of an impact IMO.
It's not the height. It's the surface area of the bottom. Let me speak metric for a minute because SAE units are stupid

If you have a square container that is 10cm on a side, then the surface area of the bottom is 100 sqcm, so 100 cc of fluid will fill the container to a height of 1cm.

If you make the container 20cm long instead of 10, then the surface area of the bottom is now 200sqcm and the same 100 cc of fluid will only fill the container to a height of 0.5cm.

If we assume our 50gallon aftermarket tank is about twice as large as the OE tank in surface area, a given volume of fuel will only fill it to about half the height as the OE tank.

So, even if the starvation height is the same, the volume left in the tank when that happens is higher.
With you on the metric system...we should have switched when it became law in the 70s...
I can see where the longer bottom surface area could cause a problem on steep inclines (all the fuel at front or back of the tank) when tank is extremely low.
But if tank height is relatively the same and the pump height stays the same from the bottom there should be no issue under relatively normal operating conditions. Doesn't matter if the tank is 50 or 1000 gallons yes you would have more or less liquid volume but the pump doesn't know or care. It's designed to pump fuel from a predetermined min/max fluid level.
On the other hand I could see an issue if operating on a 7 grade for 5 miles if someone hit it almost empty?.
I still don't get how a sump in the center of the tank will solve this problem. If someone is so low on fuel that the length of the tank is "holding" all the fuel at one end during climb or descent the center sump won't correct that issue....unless you had two...at front and back??
 

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Discussion Starter · #34 ·
For a stock tank it works as designed. We are talking about making a aftermarket tank with known issues work. Because obviously if you take time to read any of these threads the stock set up is not working with this tank and people are not being able to utilize the extra gallon's out of this tank. So yes the sump is a great idea because gravity works and will continue to work. Not to mention if someone is tuned and has larger injectors blah blah blah they can take advantage of the larger outlet than the factory draw straw to use larger fuel lines.
I've read all the threads and discussion on this tank and guess I'm a little confused. If the overall tank height of the aftermarket tank is no more than .25 inches difference from the factory tank in height then I'm not understanding what the percieved problem is everyone is talking about with pump starvation. The variance of .25 inches in height of a tank is not going to have that much of an impact IMO.
It's not the height. It's the surface area of the bottom. Let me speak metric for a minute because SAE units are stupid

If you have a square container that is 10cm on a side, then the surface area of the bottom is 100 sqcm, so 100 cc of fluid will fill the container to a height of 1cm.

If you make the container 20cm long instead of 10, then the surface area of the bottom is now 200sqcm and the same 100 cc of fluid will only fill the container to a height of 0.5cm.

If we assume our 50gallon aftermarket tank is about twice as large as the OE tank in surface area, a given volume of fuel will only fill it to about half the height as the OE tank.

So, even if the starvation height is the same, the volume left in the tank when that happens is higher.
With you on the metric system...we should have switched when it became law in the 70s...
I can see where the longer bottom surface area could cause a problem on steep inclines (all the fuel at front or back of the tank) when tank is extremely low.
But if tank height is relatively the same and the pump height stays the same from the bottom there should be no issue under relatively normal operating conditions. Doesn't matter if the tank is 50 or 1000 gallons yes you would have more or less liquid volume but the pump doesn't know or care. It's designed to pump fuel from a predetermined min/max fluid level.
On the other hand I could see an issue if operating on a 7 grade for 5 miles if someone hit it almost empty?.
I still don't get how a sump in the center of the tank will solve this problem. If someone is so low on fuel that the length of the tank is "holding" all the fuel at one end during climb or descent the center sump won't correct that issue....unless you had two...at front and back??
Correct it’ll suck fuel at a predetermined level but length does matter as at the exact same level one tank will have many more gallons, that’s the rub some have they feel they aren’t able to use this larger tank to it’s full stated capacity and have more fuel remaining in the tank then when using the oem, which they do but yes the min level in a depth measurement will be the same or close, I do think the larger tank has a tad more depth increasing the feeling of not getting to use the tank to it’s listed spec.
 

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Speaking of fuel and tanks,, here's something for those of us who are stock with the Diesel XD. Was doing a fuel gauge accuracy test after replacing the fuel sending unit.. I put 12 gal in for a totally dry tank.. gauge read 1/16 of inch about 1/2 tank.. Ok no problem, now drive until the Warning "Low Fuel Came On.. Did so just to the Right of 1/8 tank Red Zone.. At that point Combination Meter gave Warning and stated 90 miles till empty.. I reset the Trip meter to compare when she is empty.. Note.. Carry a 5 gal can of Diesel in Bed so if I'm in the middle of No Place I can get started again.. I continue to drive and by this time the Trip Meter is at 40 miles driven and the Combination Meter Now Reads ------ No miles left.. reminder initally it stated 90 miles to aprox empty,trip meter now reads 40.. So I have not traveled 50 miles when she reads ----, and the Fuel Gauge is Now Buried in the E zone past the red to the right.. No Problem
I have driven home and now parked.. Next morning go out to Start Truck,, Will not start because I can hear the Stage I Lift pump Cravitation trying to Suck fuel it can't get.. because the Fuel Sending Unit Canister where it draws from has overnight let the fuel that is in its basket leak back to the tank..
Resolved, simply put the spare 5 gal in, did the 2-4 cycle prime method for the fuel system.. Start engine.. All Good..
I have shared this for a few reason..
1. I wanted to find where the real Empty Low fuel Won't start condition existed. for my truck after 50 of driving, and shut down if left sitting for say an hour or so.. your not able to start my truck because the fuel that was in the Fuel Sending Canister bled back into the tank and now Not Enough Fuel in Tank to fill the Canister for the Pickup Tube to Prime the System.. Note: when your this low and you do not put fuel in, and you keep trying to prime your just adding more Air into your Fuel System.. also if you add enough air you can cause a situation where it will never start until you crack injector lines.. Been there done that with these XD's so when Nissan the system is designed to Purge the Air,, this is true, With a Limit to how much Air you pump in and where it get's trapped.. If in the Rails,, you will have to crack injector lines.. to purge..
2. When your that low on fuel and your running it will keep going because your only pulling about (.10 oz or 2.83 grams) of fuel rate when driving 60 mph based on 20mgh average.. Thus is why you can keep goinq until you suck her dry, But
3. But and there is always a Butt,,LOL Once you Shut down.. even after You put fuel in say shortly later after sitting you make suck some air into the system and have to prime or find a delay of engine start..
4. Bottom Line With the XD - Don't Run it Down Past deep in the Red Zone.. Get Some Fuel when She says Low on Fuel, will save you some aggravation especially you don't have a Spare 5 Gal of Diesel laying around handy..
See Pics to better understand the above and your sump Fuel Sending Unit

Enjoy
Merry Christmas and A Great New Year!
How do you release the green clips so you can take off those lines when replacing? I can not figure it out or I am just worried I am going to break them.
 
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