Hey all – Merry Christmas!

Does anyone know if the Excursion or any model of F Series or E Series has the diesel fuel tank in between the frame rails behind the rear axle? If so, can I get that tank to fit between the frame rails in my ’99 F350 DRW?

So, here is what I am up to: I have been looking at a number of options for the old Powerstroke and one of them has been Compressed Natural Gas (CNG). Seems that most folks will put the CNG tanks in the bed of the truck, but due to having a flat bed and a bed ball for towing fifth wheel trailers, I am not hip to that. Obviously having to store CNG at +3,000 PSI pretty much requires round cylinder storage tanks.

Presently my diesel tank is port side (that be on the left of centerline when facing forward towards the bow) between the frame rail and driveshaft. If we do not dwell on whatever in the world I would do regarding the exhaust, I could probably put a moderately sized CNG tank on the starboard side (yup, on the right side…) between the driveshaft and frame rail. That tank would not hold that many gallons of CNG for long trips so having a second tank located where the diesel tank is located today would be a logical approach.

Clearly, I would still need a storage tank for the diesel, and since I do not carry a spare tire under the truck anyway, that location would be a great spot for the diesel tank.

Thoughts, suggestions, input? Thanks everyone and have a great holiday season! -blake

 

Yep, the Excursion has a rear mounted tank. I'm not sure if it is a direct bolt in but if it isn't it shouldn't be hard to do. The spare tire on the Ex goes inside.

I've been eyeing it on my Dad's Excursion thinking it'll be a great addition for my regular tank. I think it's around 40 or so gallons...

 

You can still use a bed mounted configuration with the flat bed, unless you just don't like the looks of it. You could also look into a set of stacks if you want to get the exhaust out of the way.

 

A big 40 gallon, now that would be nice. I will have to go trolling around some salvage yards and take some measurements.

I am going to stay away from a bed tank. Shtuff happens, and I would not wish to accidentally puncture the CNG tank on the bed or damage a trailer when turning really sharp or trying to hook up or disconnect a trailer from the truck. I also would prefer to not lose any storage space on the bed.

Indeed, stacks would probably be the solution for the exhaust. Not sure if that is the route I wish to go, but I am working one solution at a time right now.

Thanks, -blake

 

I understand about loosing the bed space, but the tanks are sturdier than you might think. I had some half tons that we converted to run on propane about 10 years ago with the in bed tanks. One truck got in a pretty nasty wreck and ended up with a small dent in the tank, but no leaks at all from the system.

Make sure you take pics to share with us and keep us updated on your progress on this. It sounds interesting.

 

Excursion tanks are 44gal

 

If you get an Excursion tank, you might want to also grab the hitch assembly.

Though this is not personally known to me, I've been told the Ex's tank won't fit if you have a truck hitch.

Pop

 

I have yet to rebuild the engine and trans which will be a spring/summer ’09 project. Those items will take precedent over the CNG mod, but I want to make sure that I have my mods planned out so I can do the mounts, cables, hoses, you name it prep work while I have the truck torn apart to do the engine and trans. I plan on removing the side tank and installing a rear tank with new fuel lines all the way forward and will go on ahead and install frame mounted fuel filters plus do some form of an in tank fuel pump.

I do not suppose that the Excursions use in tank fuel pumps do they? Is it a no no to utilize a gasoline fuel tank if I clean it out first (that is if I do not find a diesel Excursion to steal the tank from)?

Even better!

I cut off the PoS 2” hitch that was on the truck when I bought it and manufactured my own step bumper with incorporated 2” receiver. It will not impair a rear tank – though I will keep your suggestion in mind when looking at tanks at the junk yard.

 

Blake-

Have you come any farther on this? I've kicked around adding an Ex tank behind the axle on my dually also. I don't put my tire under there so it's the most logical place. I think the crossmembers would have to be removed aft axle. Mine would be in conjunction with the existing tank. Don't know using a gasoline tank vs. a diesel tank. Maybe the sending units?

I'd like to year about what you end up doing.

 

Hey Ryan, no I have not added the rear tank. Clearly with the economy as it is and the Govt. spending like fools, I have some trepidation with spending on non-essentials right now. My 7.3L still needs a rebuild and that is were my cash is going to have to go.

Regarding the cross member, I pondered if it would have to be removed myself. As for whether you can use a gas tank in place of a diesel tank, I am not quite sure on that one. I would certainly expect that the sending units would be different... -blake

 

Bringing this back from a long time ago, but I was wondering if anyone has gotten further on their project. Im very interested in doing the dual tank and wanted to start gathering more info.
Thanks guys

 

Another place to look for a tank.The F-350 ambulances also have a rear tank

 

All the 99-09 f350, f450 and 550's in my yard are factory rear tanks. Unless a chassis is spected for a towtruck app, it will come with a rear mounted tank on all chassis cabs.

 

has anything happened with this? I'd like to mount cng tanks on my frame of my excursion.

 

The Excursion's tank is mounted behind the axle. The spare is mounted inside the vehichle. The Excursion is also shorter than a crew cab short bed F250, so not much room for a tank mounted forward of the axle unless it's custom made.

I'm sure you could get a custom fuel tank for the diesel (if you want to keep it) and put the CNG cylinder in the factory fuel tank location.