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beardedone
09-15-2008, 11:06 PM
I just got back from a short trip and checked my economy. I have an 08 Dodge 3500 dually and an Augusta. Two lane rolling hills and 95 Kph. (60 mph) Got 12.1 mpg (US). Happy, Yes. None

pmmjarrett
09-16-2008, 05:56 PM
Yer doing good on an '08 with all that new emmissions stuff.:)

beardedone
09-16-2008, 08:17 PM
I know but I wonder how it will be after the warranty expires and all that stuff falls off. Some people are getting as much as four or five mpg more. At that rate it will be environmentally friendly considering how much fuel it burns during a regen. Also the engine will last longer, another bonus.l

HappyKayakers
09-17-2008, 01:09 PM
I just got back from a short trip and checked my economy. I have an 08 Dodge 3500 dually and an Augusta. Two lane rolling hills and 95 Kph. (60 mph) Got 12.1 mpg (US). Happy, Yes. None

Was that the figure from the on board computer or hand calculated? Also, were you loaded light or heavy?

beardedone
09-17-2008, 06:04 PM
That figure is overhead, However I carefully hand calculate everything and have done so for years. The overhead and hand calculations are always the same. I tow heavy and the truck handles it like a dream. I have air bags, exhaust brake and I use the electronic shift control to gear down all the time. Works very well. (don't know why bold came on - it wasn't intended)

pmmjarrett
09-17-2008, 07:24 PM
My overhead is always 1.5-2 mpg high.

2873

None:D

beardedone
09-17-2008, 10:19 PM
Hi pmmjarrett
I got my new aluminum fuel tank today. It is 187 litres across the front end of the box. I assume you have an aux. tank in your business. How did you plumb it in. Did you use gravity feed, electric pump etc and did you plumb in a fuel filter. If so, how did you do it.

Thanks,
Gerry

pmmjarrett
09-17-2008, 11:51 PM
Yes sir. Gravity feed 91 gallons. Don't leave home without it.

I have this RDS 91 gallon aux tank (http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200306739_200306739) and plumbed it with this kit (http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200315501_200315501)

Measure your fill neck hose. Most Dodge is 1-1/2" ID. There is also a 2" dia kit available for the chebby guys (http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200315503_200315503)

Simple install. Runs from the tank drain to the filler neck. There is a ball valve screwed into the tank drain fitting connected to the hose that goes to a "T" that you put in the fill neckby cutting out about 1.5" of the hose (you want this in a place where it keeps the T fitting as level as possible). The "T" has a check valve to help prevent over filling. I also used a grommet where the hose passes through the bed so the metal doesn't cut the hose because of vibration. You can also route a hose from the tank vent through like this so any small amount of spash doesn't go into the bed. I had mine like that until I needed a short piece of the tank vent hose for an emergency repair.

I leave mine on most of the time as it doesn't set a fuel sender code like it did in my '06 Ford. I usually shut it off when parked overnight.

One of these days before the snow flies I need to route my return line to the aux tank which hopefully will help prevent some of the freeze up problems I had last winter in that 5/16" hose whenever I got a little water in the fuel.

dieselengineer
10-09-2008, 04:17 PM
How are you doing with the aux tank? I have my piped with a walbro pump. It is a pulse type so there is no problem with running the pump dry and it automatically shutoff if over pressure occurs. The DOT doesn't like gravity setups. You should always draw the fuel out the top of the tank and have a rollover valve on the vent connection. I pipe my thru a 10u spin on fuel filter. That is why I like the auto shutoff feature of the pump. Simple to use - driving along, if the fuel level is down to say half, flip the switch and watch the fuel gage go up. Watching the gage go up is the best part!

beardedone
10-09-2008, 09:34 PM
I did the gravity feed thing. Exits the bottom of the tank and I placed a shut off valve right beside the exit. It goes through the side of the box and underneath to a spin on filter and then to the "T" in the vent line. I am using a 3/8th" fuel line.

Pulltab
10-12-2008, 07:27 PM
I tow with an 07.5 dodge with the 6.7 we are near our max of 23,000 lbs and averaging hand calculated 10mpg. My overhead is always producing stupid numbers. Almost ALWAYS 1.5-3 mpg high.

pmmjarrett
10-14-2008, 06:27 PM
The DOT doesn't like gravity setups. You should always draw the fuel out the top of the tank and have a rollover valve on the vent connection.

Gravity feed is legal. There are a few aux tank manufacturers (albeit with very very pricy tanks) that have pushed this propaganda and Transfer Flow is one of them that interprets a certain law to their liking. In particular ... FMVSS 301

CFR 393.65(d) (http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&rgn=div5&view=text&node=49:5.1.1.2.36&idno=49#49:5.1.1.2.36.5.12.1)
(d) Gravity or syphon feed prohibited. A fuel system must not supply fuel by gravity or syphon feed directly to the carburetor or injector.

An Aux tank feeding to main tank is not feeding to carb or injectors

CFR 393.67(c)(5) (http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&rgn=div5&view=text&node=49:5.1.1.2.36&idno=49#49:5.1.1.2.36.5.12.2)
Fuel withdrawal fittings. Except for diesel fuel tanks, the fittings through which fuel is withdrawn from a fuel tank must be located above the normal level of fuel in the tank when the tank is full.

My tank is below the bed rails, has a rollover vent valve on top, a check valve in the feed line and a ball valve to completely shut off fuel to the gravity feed system.

My trucks have been inspected by the DOT on several occasions and have passed annual Federal safety inspections performed by outside shops.

My current truck also passed a CVSA Level 1 inspection (http://www.cvsa.org/programs/nas.aspx) in April and has the "get out of jail free" decal on the windshield. CVSA Level 1 is the most comprehensive driver and vehicle inspection and includes the fuel system.

What I am always asked about the aux tank when they ask if it's gravity is.."is there is a check valve in it", say yes, show them the valve and it passes.

dieselengineer
10-14-2008, 09:42 PM
With a gravity system, the level in the aux tank can be and will be above the height of the OEM fill cap and OEM tank vents. With my luck, one of these will surely leak sometime down the road. I feel more in control if I can control the level in the OEM tank via a pump. The pump setup has a spring check (anti siphon) and a filter. So I am actually filtering what goes into the OEM tank at a higher level then the very small OEM stock filter. The OEM tank is never above the OEM maximum level. Also the ECM does not get confused. And like I said, I really enjoy watching the fuel gauge go up. With a gravity system, I would miss this joy. :)

Pulltab
10-14-2008, 09:57 PM
LOL very true Diesel! :) I also use a pump, I like the control also.

pmmjarrett
10-15-2008, 12:13 AM
The check valve in the gravity system keeps the fuel below the OEM gas cap. I can take off my cap when my aux tank is full and not spill fuel.

Fuel from the aux tank flows pretty slowly through the 5/16 line and check valve from the aux tank. If your factory tank is near empty it takes many many miles to refill. You can leave the aux tank shut off and only turn on when you stop for a break and shut off next time you stop or when it's topped off.

Some trucks like my 06 F350 will throw a code if left on constantly, no problem on my 04.5 Dodge 3500.

I have run over 100,000 miles this year so far with this tank and gravity setup and no problems. I leave it on constantly while traveling and shut of the ball valve on the tank when done for the day.

One thing I should do with the way I run, that I havn't yet, is to run my return line to the aux tank.

For extreeme cold weather keeping heat in the aux tank or a pump setup is needed because the check valve tends to ice up in sub 0 temps if there is any moisture in the fuel at all which means pulling the line and getting the slush out.

jimtoo
10-15-2008, 12:32 AM
Hi pmmjarrett,
The return line from injector pump to aux tank is a good idea in the cold weather climate like you are in a lot of the time. But the only thing is, I am pretty sure your injector pump will be returning a lot more fuel to aux tank than what will gravity feed to your main tank, so you would need to be sure you do not over fill your aux tank by doing this. This is just a thought I had, and if you do make a manifold to reroute your fuel return line to aux tank and depend on gravity feed to main tank, keep a close eye on it.
What do you think?
Oh,, and the GM will set a code if tank stays full (gauge stays on full) for to long of a time while driving also. Just turn off aux tank and drive a little more to get main tank or fuel gauge to come off of full and it goes away. It likes to know it is using fuel I think and not running on air.
Jim M

Forrest Fetherolf
10-15-2008, 09:58 AM
I have the RDS combo tank with gravity flow, I installed an in-line Murphy diesel fuel solenoid valve in the fender well and an on-off push button switch with indicator light on the dash. I can control fuel transfer with the switch and the indicator light let me know the valve is open. I have found it best to run the main tank to 3/4 full, then start to transfer. This method allows me to monitor that the fuel is transferring and the ability to shut it off when main tank is full. The switch ability stop the transfer allows me to keep "reserve fuel" in case I get caught between fill-ups and the main tank gets real low.
The Murphy valve, switch w/light, and wiring cost about $60 and 1.5 hours to install. Wiring is simple.

Forrest

Forrest Fetherolf
10-15-2008, 11:45 AM
FYI..........Fuel transfer switch (black button beside orange LED under A/C vent) and valve (under fender well) photos.

Forrest

pmmjarrett
10-15-2008, 09:21 PM
Hi pmmjarrett,
The return line from injector pump to aux tank is a good idea in the cold weather climate like you are in a lot of the time. But the only thing is, I am pretty sure your injector pump will be returning a lot more fuel to aux tank than what will gravity feed to your main tank, so you would need to be sure you do not over fill your aux tank by doing this. This is just a thought I had, and if you do make a manifold to reroute your fuel return line to aux tank and depend on gravity feed to main tank, keep a close eye on it.
What do you think?

Jim M

Jim, I've wondered about that too. One would have to measure the volume of gravity flow and the avg flow from the return to give it your best guess.

I may not be running this truck this winter now. Am trying to close a deal by Friday or Monday on a nice, well maintained, low profile 1998 Ford F-800 to build into a tow & haul truck this week. Haul one trailer on the bed and tow one behind, double dipping baby:D

2991 2992 2993 2994 2995

Specs

26k GVW
7k steer axle
19k rear w/3.54 gears
5.9 Cummins, P7100 pumped 12 valve
Allison 540 series 4 speed automatic
19.5 rubber
dual 40 gallon tanks.... will be dual 150s if I have my way with it.
184k miles
power windows
ice cold AC
cloth seat
hydroboost juice brakes
Runs and drives great, Fresh paint, 75% rubber on rear, needs new steer tires, no rust, one owner southern truck with all maintenance records since new and still has original owners manuals........ And they're only asking $3000 for it:eek:

Detmer
10-16-2008, 09:48 PM
Does anyone know the difference between a auxilliary tank and a transfrer tank? Are they built differently?
Is it possible to gravity feed what is called a transfer tank if the tank is vented and has a drain fitting on the bottom to use for the feed?

If this is possible what I am considering using is a UWS TT-45 combo tank but they list list as a transfer tank. This tank is 45 gallons and has a nice size tool box and is reasonably priced.

I am having a hard time getting the RDS tank that I would like due to the shipping costs. If Northern Tool does not stock it locally they drop ship it from the factory and then the shipping cost are pretty steep these days.

Vinny

pmmjarrett
10-17-2008, 05:07 AM
auxiliary tank has fittings to hook up a feed line with standpipe, a return fitting and fuel guage so you can run you truck on the tank

transfer tank has a 2" NPT bung to hook up a fuel transfer pump to transfer fuel to other equipment as a portable fuel station for job sites or the field.

aux / transfer tanks like mine can be used either way.

Both syles sould have a tank drain and vent

Detmer
10-17-2008, 12:17 PM
So the real question is can a transfer tank be used to gravity feed the truck tank? Would this be considered legal?

Forrest Fetherolf
10-17-2008, 06:42 PM
So the real question is can a transfer tank be used to gravity feed the truck tank? Would this be considered legal?

Cursor up to #12 post to pmmjarett post. That will answer your question.............legal for diesel, illegal for gas. Transfer tank and axillary tank are synonymous.

Forrest