07-14 38 Gallon Tank swap install thread

Wanted to update this thread. This was during the summer. A full tank on the LRA 46 netted me 653 miles before the low light came on. This was with 80/20 highway/city driving with a few times towing my bote to local lakes fishin. I believe with the low light, there should be about 5 or so more gal in it so 700 miles is attainable.

Cheers.

 

so, i've officially found a huge downfall to the stock 38 gallon swap. i recently went to fuel up and can't. no codes, but pump shuts off immediately. tried two other gas stations...same thing. did some research and found there is apparently an issue with a piece of baffle breaking free and causing the fuel limit vent valve to stick not allowing air to flow to the charcoal canister and in turn causing fuel to not fill but instead overflow out the fill neck. this valve is part of the tank and so far the only fix is a new tank. wtf toyota!!! so i got one year of use out of my $1400 dollar conversion and now i have to put my old 26 gallon tank back in for a road trip on saturday.

found multiple threads about this in 3rd gen section and on tundrasolutions

once the 38 gallon tank is out, i'll hopefully figure out a fix or bypass or go completely unsafe and punch it out.

 

Well that sucks! Hope you can fix it and works out for you!

 

@831Tun Warren didn’t you have this issue? I know you didn’t replace the tank, what was your fix?

 

Yeah @jc153, my problem was the inertia valve got stuck in Sedona. Made fueling up to get home a nightmare. I ran the tank near empty and dropped it. I removed the anti-siphon "bullseye", to access the valve, stuck a screwdriver in and the valve popped right open. I figured it would just happen again so I disabled the valve with a creatively improper application of the screwdriver.

 

Very interesting thread! When I shopped for my Tundra in 2015, it was to replace my Tacoma as I replaced our 4,400 pound camper with a 6,600 pounder so needed the V-8 in the Tundra to pull her. I found the 2014 Tundra used but in great shape so saved a ton buying her...I never even thought to see how large the gas tank was, wouldn't Toyota have one of sufficient size? (Nope) It sucks having to start looking for a place to refill while towing every 2 1/2 hours (especially in our Colorado mountains where the gas stations are usually not large enough to refill with a 34 foot camper on the back.)

So I got my Tundra paid off and looking around at options...the Ford F-250 has a big 6.7 gas engine with a 48 gallon tank option...sweet! So I built one for towing with other great options (TONS more than any Tundra)....then got to the last screen....$74,000....holy sticker shock Batman! That's more than I paid for my first house in 1990!!! That's not going to happen.

So I'm looking at either trading in my Tundra for a new one (or used with the larger tank) or just replacing the tank with at least a 38 gallon Toyota or a 46 Transferflow. It's a job above my skillset so getting a price from a local installer Transferflow recommends.

 

i wouldnt do the transfer flow... but thats my opinion.

 

why?

 

He gave a little comparison at the end of his original post.

 

Starting to research this swap a little more and came across some of the issues with the vent valve sticking and seeing if this is an issue still?

also- was originally thinking of trying to pickup a tank from a junkyard but looks like that might be asking for trouble, and when I try to look tank up at Toyota is says no longer available

would really like the extra range but don’t want to sacrifice reliability

 

mine just happened right before christmas and it was on a tank that i just bought a little over a year ago, so yeah, still an issue

 

Man that’s frustrating. Hate to hear that.

 

I have a question for the experts here. I was able to track down a 38 gallon tank from a local junk yard for 185 bucks. Score! However, it looks like they cut some of the lines when they removed it. You can see in the pics. Can anyone tell what all I'd need to do this? And what I can re-use? Thanks

 

the lines to the pump are ok, since you can reuse your existing. the first couple, they kinda screwed you on and now you'll have to bandaid because those are part of the fuel tank assy. big line goes to charcoal canister and the smaller line goes to your overflow on your filler neck

 

for once I'm glad I had the small tank when I installed my sliders or else it would have been a PITA
if I upgrade to bigger tank size, I think the Toyota oem is the best. The vent valve sticking seems to be an issue that has nothing to do with the swap itself.

 

Thanks so much for the info. Are these the two that I'll need?

 

those are the two you'll need to splice onto your existing ends. the two on the pump (big white round deal) are the ones that you can unplug from your old pump and reuse

 

correct. the swap has nothing to do with the valve sticking. they are defective. unfortunately, part of the tank, so risk it happening or punch it out ahead of time

 

Would I be able to take them off the old tank and use them? In your pic, they look identical.

 

Just picked my 38 gallon tank up today and will swap this week. Lots of useful info in here, you guys are great. Where is the anti siphon valve? Filler neck? I think I’ll take care of that prior to installation.

 

you would just have to figure out how to connect the hoses to the pieces on the tank

 

I was able to pull the larger hose for the charcoal canister off my old tank and put it on the 38 gallon tank. For some reason, the one on the 38 gallon tank is a little shorter which made it difficult to connect and also puts tension on the connector clip. You might be able to pull the thinner hose off as well.

 

Thanks for the info!! I'll attempt this once I get everything I need and it warms up a little, which here in the Midwest, might be an eternity...

 

Would like to hear how the installs go!

Would also like to hear more on being able to bypass the vent

also was wondering if anyone knows why the fuel pump for a 38 gal tank has a different part # then the 26 gal tank?

38 gal - 77020-0C170

26 gal - 77020-0C120

 

How does that hose pull off? Did you pull the whole vent or were you able to get just the hose.

 

Just the hose. its pretty snug so there's going to be some huffing and puffing before it comes off. There is an o-ring on the barb so be careful not to damage it.

 

Only difference I could find was that the sender had a different part number. The pump itself is the same. I could see a different number for that reason but I also read the assembly is the same but maybe a different manufacturer

 

the two fuel lines off the 26gal tank will work on the pump... i ended up using my 26gal tank fuel lines

 

I’m guessing they sneak down the side where the new front part of the tank is on the 38 gallon, yes?

 

Where did you route the lines from the 26gallon to get to the main and return attached to the frame ?