i need to drop the rear belly tank on my dually. the question is just how much of a pain is that going to be???
thanks for the help

 

The skid plates are all that holds the tank up. So when you unbolt them you have to be able to support it till you get the fuel lines and guage wires disconnected. Also you have to disconnect the fill spout hose.
The cross member is in exactly the wrong place to make any of this easy. Also the funky little fuel line clips are a pain to remove when you can not see what you are doing.
There is not much extra hose or wire on the tank connections, so you can not let it down very far before they start pulling on the sending unit.
Also there is probably a large amount of dirt on the top of the tank to fall in your eyes when you are trying to get it all unhooked, safety glasses will help some.
Some trailer hitches will not let the tank out of the frame either. I have a 12,000 pound hitch that has to be dropped before I can take my tank down.

One thing that helps is to get all the fuel out you can. The lighter the tank is the easier it is to remove.

I rate dropping the tanks at a 4 on the difficulty scale only because they are big and awkward, in a difficult location, and have connectors that are hard to get at.
However I also rate dropping the tanks at an 8 on the frustration scale for the above reasons.

I love my dump bed.
I just removed the rear tank on my truck three weeks ago.
I ran the bed up, disconnected the lines and hoses.
Went under the truck and dropped the hitch, skid plates and tank.
Took me about 35 minutes.
When I dropped the tanks the first time with the stock bed on it each tank took about 2 hours.

Also if you go down to a parts place and get some fuel line clips so you can see how they work it will make it easier to unhook the lines. Also with a spare you can just break the clip to make removal easier.

 

No experience with the dually but I just pulled the tank on my one ton SWR for the second time and here's my 2 cents worth of opinion. It's faster and easier to remove the bed (6 bolts, unplug wiring harness, disconnect gas fillers) so you can see what you are doing with the tank and can reach all the connections etc. You can also blow or vacumn all the loose dust, dirt, and grime out of the way. Actually, with the bed off and the tank empty it's easy to take the tank out the top. (2 bolts) If you are like me and doing it for the first or second time where you will really save time is when you put the tank back in. Hook it all up and then put the bed back on.

 

I second the bed idea. I usally just raise it up if I am working solo as it is hard to do singlehandly.

 

i would think that would be a good idea, but i have a 100 gallon fuel tank back there

 

Neither of my tanks will come out through the top on my 86.
The frame is not wide enough for the rear tank to come up.
I do have a 44 gallon rear tank though.
The front tank is under two frame crossmembers.

Still it is almost worth pulling the bed to get at the connections and not eating lots of dirt trying to get at them from the bottom. I would do it that way if I were dropping both tanks.

I guess the 100 gallon tank in the bed does throw a wrench in that idea though if it is for on road fuel and plumbed into the truck.
My 100 gallon bed tank is for off road fuel and lifts right out.

 

The rear factory tank on my 91 F350 4X4 crew is a 19 gal tank and one side has to be lifted out before the other will lift up to clear the frame when removing it from the top. I can see where a larger tank would be a different ball game but once the connections are removed it is relatively easy to drop an empty tank out the bottom like Dave described in his first post. The forward 19 gal. tank on my truck is also under 2 cross members and can only be removed by dropping the skid plate.

 

Quick question on the rear tank while we're on the subject - does the tank have a drain plug? I have some crap in the tank (not sure exactly what it is, but it was a PITA when I ran the tank low and then had to bleed the crap out of the fule line - smells almost like kerosene... probably water with a little disolved diesel I guess), and I was hoping to drain it. I tried pumping the tank out by hand, but that seems to have made things _worse_! I don't want to have to drop the tank to clean it...

Thanks,
Chris (1990 F250 4x4, 7.3 IDI)

 

Some model years may have them but there is no bottom drain plug on either of the factory tanks on my 91 F350.

 

ctann there is no drain plug.

Drop the tank, remove the fuel guage sending unit and swab it out with rags on a stick.

Then use a mirror and flashlight to inspect the interior for rust and the like.

 

Thanks, thats what I was afraid of. I'll probably just hang on until my next service and get the shop to drain it - I'm sure they've
got a suction pump that'll get all the crap out.

Chris.

 

The only way to get it all out is to drop the tank.