I have a 1977 fj40 and was just wondering any pros or cons for moving my fuel tank underneath the truck. or leave it set up underneath the seat?
Pros and cons for moving gas tank on fj40 (1 Viewer)
- Thread starter rmiranda76
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pros would be that it is pretty safe from damage inside. Toyota put it there so it's all plumbed and the filler neck is already there. Some potentially complicated modifications aren't needed if you don't move it.
cons is that your fuel is inside. On a perfect working system it's not really an issue, but if you disable the vent system or you have a problem it can be smelly at best and downright dangerous if very modified and you have a flop or rollover.. It also frees up room under the seat for storage and lowering the seats if you move it.
FWIW - on my rock crawling rig it was outside (FJ55) and now it's in a fuel cell inside. On my road going rig (FJ45) it was under the seat and now it's under the bed.
cons is that your fuel is inside. On a perfect working system it's not really an issue, but if you disable the vent system or you have a problem it can be smelly at best and downright dangerous if very modified and you have a flop or rollover.. It also frees up room under the seat for storage and lowering the seats if you move it.
FWIW - on my rock crawling rig it was outside (FJ55) and now it's in a fuel cell inside. On my road going rig (FJ45) it was under the seat and now it's under the bed.
I put mine under the rig between the frame rails in front of the rear axle.
The ONLY reason I did this was because of the motor, trans dual case set up ended up cutting into the stock fuel pan.
It was a SH!T TON of work to do what I did!! I would NOT recommend going that route. However, the upside is there is more storage space, the weight is lower and centered and now that its done... I like where it is.
Biggest down side is the work required to get it there.
Those rear tanks are pretty cool. Not an option for me as I moved the axle so far back, but an option for most.
Here's a pic of where its at w/ the tub off.
The ONLY reason I did this was because of the motor, trans dual case set up ended up cutting into the stock fuel pan.
It was a SH!T TON of work to do what I did!! I would NOT recommend going that route. However, the upside is there is more storage space, the weight is lower and centered and now that its done... I like where it is.
Biggest down side is the work required to get it there.
Those rear tanks are pretty cool. Not an option for me as I moved the axle so far back, but an option for most.
Here's a pic of where its at w/ the tub off.
It is not dangerous at all inside no matter if you flop or not . I've flopped my rig with the tank under the seat over 50 times and never had a problem . I've rolled it completely upside down lots as well and never really have issues (other than a little spilled fuel and oil) I do always carry a fire extinguisher and try to use common sense whenever possible . I wouldn't be afraid or worried for any reason about the stock location .
A con for moving it would be that you can't move the rear axle back (at least not much) to extend the wheel base if you put a big tank under the body.
That being said, I really like having mine under the body.
That being said, I really like having mine under the body.
Talk to my buddy that spent over a month in a burn ward because he slid his stock 40 sideways into a tree and it went kaboom..
It can happen, but is not likely.
and, as I keep saying, it's a whole lot less safe if the vent systems has been modified or disabled or it's otherwise not in good repair.
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Yep, a long time ago I had disabled the vent on my tank in my 40. One day I came home to find gasoline dripping from my rear main seal. The tank had pressurized enough to blow past the carb needle and flood the engine with fuel.
Way stupid, but at least all I found was a puddle of fuel instead of something more dangerous..
Exactly the modification that I was speaking of.
I use my FJ to pickup wood at Home Depot or drive the kids to get ice cream. No danger for my gas tank exploding.
I recently moved my stock tank from inside the cab to a under mounted tank. The big reason for me was to be able to drop my seats down lower. The stock tank makes it difficult to work around a cage and keep everything low. I ended up with a 15.5 gallon aluminum tank mounted under the rear deck area. I was able to use the factory filler neck location.
Kentex Rick
SILVER Star
Dude, this is old but funny as hell!
I've now rolled /flopped more times than I can count at this point. Why do you find it funny? I never intended it that way. I guess I just use my rig a little differently than most on here. I still think the tank under the seat is perfectly fine, even upside down most of the time. I'm pretty good at getting myself sorted out so I don't mess around too much if I am completely upside down as all the oil tries to run out of the transmission. Most of it stays in the motor for some reason?
Kentex Rick
SILVER Star
Sorry, man. I laugh at all my friends when they roll! I just prefer to stay upright!
Everyone is different...
Where did you get your tank?
