My 1970 F250 Ranger XLT is mounted on a 1973 Highboy frame. I've seen many trucks in the 73-79 range that have a rear frame mounted gas tank, but when you look at my frame there is a crossmember directly in the center of where the gas tank would normally mount. Is this something odd or was this model just not designed to use a rear mounted tank.
I've tossed around the idea of moving it back to put the tank in, but don't want to end up with other problems like how to reinforce the area to prevent frame twist. Although the other trucks I've looked at don't have it, so what keeps their frames straight?


Signed,

Confused

 

Good question, I've wondered the same thing.

 

>My 1970 F250 Ranger XLT is mounted on a 1973 Highboy frame.
>I've seen many trucks in the 73-79 range that have a rear
>frame mounted gas tank, but when you look at my frame there
>is a crossmember directly in the center of where the gas
>tank would normally mount. Is this something odd or was this
>model just not designed to use a rear mounted tank.
>I've tossed around the idea of moving it back to put the
>tank in, but don't want to end up with other problems like
>how to reinforce the area to prevent frame twist. Although
>the other trucks I've looked at don't have it, so what keeps
>their frames straight?
>
>
>Signed,
>
>Confused

I know where you are comming from about that cross member and the support if it is removed. This probably won't help most but this is what i did. I took out the last cross member on the frame to install a tank back there. I took a 79 Bronco tank and mounting gear and turned the tank so the fill is in the rear. I made a frame out of 3/4 inch square stock and bolted that to the frame of the truck. I made it so i have the tank as high up as i could without hitting the floor of the bed. The tank does hang down a little more then most would like but not lower the the axel. To reinforce the frame i took a 1/2 inch plate and welded it to the rear of the frame for support and i put a pintle style hitch on it. I have a mason dump body on this truck and i swapped in a dana 70 dually rear and springs. I have towed a 12,000lb chipper (lots of tounge weight) behind it, i've had 2 and a half tons of stone in the back and i've never had a problem. If anyone has any questions feel free to ask.

Jeff

 

I have a 73 crewcab SB with the narrow frame and heres what Im planning on doing. I took the rear crossmember out of a junk truck and I am going to move the orignal foward and install the one from the junk truck in the back and space the two far enough apart and in the right place to mount a 78 bronco tank with spout going where a factory tank would in a wide frame. The bronco tank is about an inch and a half too wide so Im going notch the bottem frame rails just enough to get the tank to fit. I also have a trailer hitch that should act kinda like a truss to suport the frame. Leadmic

 

...and what about the spare tire holder that is not there?

 

You put the spare tire in bed and call it good.
Leadmic

 

I'm dealing with trying to mount a rear tank on my 73 F250 4x4 and I think you might be able to move the tank forward enough to clear that crossmember.

Mine is a custom made tank that I pulled from a junk yard, but I think it's close to the length of the standard tank. I think you can go up as far as where the shocks mount to the frame.

 

leadmic,
Aren't you worried about weakening the frame aft of the rear axle? It seems that if you hauled a heavy load the frame might buckle. I have thought of doing the same (notch the frame a little) but thought the if the frame should buckle at the same point you have 30 gallons - it would not be a fun situation.
Todd

 

Todd Ive thought about it a lot and first let me say I dont like the Idea of notching the frame but mine is a short bed and the frame is huge on thease trucks also the side rails on the hitch that I have run
along the frame. Also adding another cross member will add more strignth. You see I need more fuel and I hate having the fuel tank in the cab. I gess if you were hauling max G.V.W. (like a heavy camper) alot or all the time you could glove the frame at the notched area but your not taking that much metal I dont think their would be a problem. Ill let you how it goes. Leadmic