My opinion is the nylon sounds good, every plastic based product does get old and brittle in time and will fail.
I do not know anything about the lines you are talking about ..... just not interested in them.

I am using a fairly new product called nicop.

It has all the proper safety certifications to be used for fuel, transmission fluid or any other automotive use.
It is pretty flexible and easy to work with compared to steel lines. Economically it is pretty cheap. This package I ordered from Amazon along with the fittings I needed. Because it is softer it is easier to get a good flair on the end with no leaks .... steel is a little tougher.
The manufacturers claim it will last a lifetime and never rust. ...... I do not think it has been around for a lifetime yet though .... so not proven.

I can say that most car builders that restore or create custom Hot Rods .... I would assume the 4x4 truck builders are using the same.
The same builders that use it professionally are also using it on their own cars and family members cars because of price and quality.

So thats my opinion and what I use on all my own older vehicles. .... A little extra work to actually cut, bend, flare making from scratch, but if they last a lifetime why not?

 

I haven't looked into using copper line but I will definitely check it out, thank you!

 

Keep in mind that most if not all medium/heavy duty trucks (semis) use a nylon fuel line. They hold up for million miles or more. The biggest thing with nylon is to make sure it doesn’t rub anything, and it’s kept away from high heat sources.

 

Another vote for nylon. I used them on my 02, I did all lines and it was a breeze. Held up just fine as long as its secured properly.

 

Not trying to revive an old post but I don't want to make another post about the fuel line and have not been able to find anything on the internet but what diameter should the fuel line be and how many feet of line should I get if i was to get unbent line?

 

I do not know the answer to your question .... I will tell what I do know.
The size you want to purchase is the same size you are replacing .... you will want to use the same size fittings to reconnect it.
The rolls typically come in 25'-50' lengths ..... 25' is long enough for one trip but not long enough for 2 trips. At least I doubt it .... tank connections are somewhere near the middle of the truck so maybe 25' is enough?

I do not know about your truck specifically, sometimes the return line to the tank is smaller diameter then the supply line .... you would need 2 different sizes of line if replacing both and if they are different. .... My Dodge Caravan is. .... Think my Chebby truck is also, not positive though.

You just want to stay with the same size as what you are replacing .... sometimes you can just reuse the old fittings on the new line, or purchase new ..... If you start converting one size fitting with a adapter to fit a different size .... gets expensive quick.

Just a heads up, I took this photo as a demonstration to someone that was complaining the unbent line would not look good on his custom project .... not sure what you think about that.

This is a example of how you can straighten the line .... drill a hole width wise through a 2"x4" and as yo unroll it pull it through.
And this is a poor example because I have 5/16" line and a 1/2" drill bit .... I just kinda wobbled the hole out so the line would go through but is to big of a hole for the line .... right size drill bit and the line will be straighter as you pull it through ..... you can make it straight, just depends how straight you want it and how hard you are willing to work at it ..... for me on the fuel line to my 49 Dodge truck, it was straight enough.
I still had to add the bends to it as it was installed .... used the old line for a template.

If it was steel line, would never be able to roll it up for shipping or unroll it for installation ... steel line would kink .... The larger the nicop line the more difficult it is to manipulate by hand .... but you can massage it and shape and form it, it is easier to work with then steel and last longer. ...... Smaller 1/4" lines for custom dual carb setups, can easily bend by hand and make it pretty.

 

Thank you for your reply man, it is very informative but I think I am an idiot and may not need to replace the steel line in my truck.

 

So I am an idiot and assumed that the fuel line that goes from the fuel rail all the way to the pump is all one line such as the feed line. However, that is not the line I need to replace.

The lines with the arrows pointing towards them are the ones I need to replace but I have no idea what these lines are called.

 

The 2 big lines look like charcoal canister lines

 

Looking at the photo ..... As much as I prefer to upgrade and make something better .... Those lines you need to replace I would be looking for exact replacement nylon lines. ..... Will be a un-needed headache trying to replace those fittings with metal replacements.

I feel like if it was me, I would feel stuck with the replacements offered .... I would choose nylon over steel.

 

So that line I was looking for is the feed hose: Amazon fuel Hose this is link to what it look like on amazon. It is a sort of plastic line that separates the hard steel line from the fuel pump. Idk its exact function beyond that.