I’ve given up trying to make my flareside bed work. The bed sides are completely rusted everywhere and the fiberglass fenders have large cracks in them. I found a used 6.5 ft straight bed from another 84 f150. A few questions:

Will this directly swap onto my frame? My truck has a rear hitch that was mounted to the frame and it’s the perfect distance for the flareside, just want to make sure I can still use it.

Do I need to put the bed on wood blocks or anything to get the correct height to match the cab?

Ive attached a few photos of the bed I’m looking at Facebook

 

Should bolt up and line up. No blocks unless cab is raised. No promises on the hitch. If you have the stock bumper, style side has a different bumper.

 

You will have to rig the bolts unless you find some factory ones. The original bolts were metric and a shoulder bolt. This is so they could torque down on the bolt and it would not squish the tubing under the bed. It has a very large hole in the bed, and a small hole in the frame.

I just use regular bolts with a large washer. I believe 1/2 standard bolts are what I used and fit the frame fine. The large washer makes it work over the large hole in the bed. Just don't get too crazy when you tighten them down or you will squish the bed tubing together.

 

I hope that style side bed has the fuel door to the front or you will have to come up with a way to fill the 16 gallon front / side mounted tank from a rear fill door.
OR
Find a 19 gallon rear tank and all the parts from a style side truck.
You will need the cross member just in front of the rear tank as it is different than the flare side one to take the tank straps.
Then you would just need to extend the fuel line and the sender wires to the rear tank.
Flare sides never had a rear tank from the factory but I know first hand on that cross member .... I run dual tanks on my flare side.

Your bed sounds like what mine was before I did all the work to fix it.
The bed side bolt lip was not that hard to make but I did not have the money for the bed cross rails & sills ($1000) so I used the style side long bed metal ribbed floor for my bed floor. Cut the sides off, cut it shorter and fitted the steps to the front bed and did the same for the rear sill.

What is nice is I dont have to treat the wood every year or what I place in the bed and hurt the wood.
The LineX was already on the parts truck bed floor and I kept it.
Dave ----

 

Wow thanks Dave. Your bed looks great! Thanks everyone for the advice. I didn’t even think about extending the tank line. I only have the original 16 gallon tank and the fuel door for my flareside was in the front. I didn’t know the styleside fuel door was in the back!

 

On the style side beds the fuel door could be front or back or both (dual tanks) even on the short bed trucks, it was only the flare side bed that had the front only tank.

So that is why I asked if that style side bed had the fuel door front or back or both?
If front then not an issue hooking up your 16 gallon tank.
If the door is to the rear then I would look into ditching the 16 gallon front tank and finding the parts for the 19 gallon rear tank and just extend the fuel line & sender wires.

The other thing to note is the fuel doors & box with the neck are different between the flare side & style side beds.
They are different sizes and shapes. Because of the size the box and the neck are matched to the door size.
The door bolt hole size different

Silver door is the style side, brown flare side


Style side door, box & neck. The neck could be used on either box but the box & door have to stay together because of the bolt holes.

Also note in the 2nd to last picture of the rubber hose. There is a plastic vent hose inside it that needs to stay in place if not you will have trouble filling the tank.
I made SURE the vents for both tanks where in place and I can fill my tanks a full force.
When you use 2 trucks to rebuild 1 from the ground up you learn a lot
Dave ----

 

Ok lets see if I can post pictures here on the rear tank.
Yes the front tank uses 2 straps on the bottom and wedges it to 2 cross members to hold it in place.

That is a 16 gallon tank and no you cannot install a 19 gallon tank in its place on a short bed truck I tried.

Now on to the rear tank. All the parts I used were from my parts truck that had dual tanks.
Because there is no cross members to wedge the rear tank to so it has 2 sets of straps, 1 set on top and the other on the bottom.
The straps fit into the cross member just in front of the tank and it is different than the non-rear tank cross member.
The cross member is a bolt in so is a easy swap.


Again everything is from the rear tank from my parts truck.
I believe junk yards punch holes in the tanks to drain them but that makes it easy to drop the tank down to get the straps, filler hose, neck & box / door if needed and get some of the sender wire to splice into your harness.
You can get some metal line to go from your metal line using a short hose & clamps to the rear tank.
Pick up a new tank & sender and bolting into your truck and you should be all set.

If you need more information just ask and I will see if I can answer them.
Dont think I have any other pictures of the tanks installed other than maybe what I did on the filler necks to work from what I had.
Dave ----

 

I’m swapping in a 29g plastic SD tank, but it will hang below the frame. But I did that because my axle swap put the rear shock mount where the rear tank goes.

 

Did you ever figure out the sending unit you will use with that tank? That will be the complication on that tank swap that may stop the whole thing.

 

The resistance matches what my gauges need. Not sure that it would be right for an 80-86.

 

I think what Dave is saying is it will read backwards from what ours dose.

Also are you sure on the resistance / ohm range?
I thought that was off also from what I have seen posted.

Is there some reason why you could not use 1 of our senders with the larger opening for models that use them (EFI?) and drop it into the SD tank with out the pump? Unless you can use the pump then drop in the whole unit.

It would be nice to have say a 20 to 25 gallon rear tank, yea i know of the 38 gallon, but I wanted to run the under tank spare tireand cant do that with a larger tank. Then you have to deal with not having a sender that will work with said tank.
Right now both tanks are factory so should be able to get parts (senders / tanks) when needed.
Dave ----

 

i can measure it out. Should work with a frame or engine fuel pump. I’ll see if the float resistor can be flipped. I have senders from 99 and 08. I measured the 99 and they are right for OBS.

 

That's right you are making a "Frankenstein truck" using the OBS cab and innards so you are right the later (87>) sender would work right with your gauge cluster.
Dave ----