Gas cans on roof

[GR8Santini]

17.9 total gallon tank. DTE is a ESTIMATE.
As DTE turns to zero, you still might have range left. DTE is based upon what you did (driving pattern since you reset DTE) & what you have remaining (remaining fuel).

The DTE calculated that shows 0 was based upon:

• Learned driving pattern since you last reset DTE (ex. going down county road, pull out & pass someone @ full throttle & your MPG & DTE probably adjust within a mile of you being back in your lane)
• Miles per gallon you were getting
• Actual Fuel remaining
• Speed traveling

Suggest when you get low DTE to change to a conservative driving pattern, reset DTE, & you now might have better estimate of remaining range. Beyond zero DTE you have exceeded the margin for what Toyota could help you with.

The EV comments are interesting. Until solid-state batteries come along, the current EV batteries are as finicky as anything. External factors really come into play with EVs much more than gas vehicle. Work great in CA, not so optimal in Maine or Arizona.

Super cold weather kills range. You might park outside @ 40 degrees w/ 3 miles left DTE, stay overnight & wake up @ 12 degrees & the cold-sink effect on the battery is now @ negative battery voltage available. Same goes for high heat driving - especially slow speeds in city as road material - concrete versus blacktop - absorbs high radiant heat & transfers to the bottom of the vehicle(battery) & can steal range. The on board vehicle systems does its best to not let these factors hurt the battery, & that safety is @ expense of DTE. NiMH are decent in heat & cold (what’s in LC), where Li-ion are very susceptible to cold sink & runaway heat issues - but they hold much more energy for their size than NiMH.

 

[Mopper]

THEORETICALLY...

My understanding on the tank is that the well in the tank is intended to hold ~2.5G while parked on a level surface (to provide a thermal sink for the fuel pump). So 17.9-2.5=15.4. 15.4x20(say)=308 miles tank range as a sanity check. Therefore, Empty for DTE is at/near the 2.5 gallons from dry, the same spot as instrument fuel gauge zero. How much additional fuel can be pulled from the well is essentially a function of how level the vehicle is.

@Sugarloafer80, you get some outstanding economy and it seems you've got a repeatable trip, but you're right at the ragged edge in your scenario... traffic jam can only last 2 hours, not 2.5 sort of thing...

Edit: I've skipped the major variable - where is "1-click full"? How repeatable is 1-click full? Across pumps and vendors? Presumably, wherever perfect 1-click full is exactly 17.9G and any additional fuel genuinely extends range (and endangers vapor canister, etc) "Neck-full" is at least repeatable somewhat. What do pilots do for temperature influence on volume? ....they go by weight, don't they...

 

[MSINAL]

17.9 total gallon tank. DTE is a ESTIMATE.
As DTE turns to zero, you still might have range left. DTE is based upon what you did (driving pattern since you reset DTE) & what you have remaining (remaining fuel).

The DTE calculated that shows 0 was based upon:

• Learned driving pattern since you last reset DTE (ex. going down county road, pull out & pass someone @ full throttle & your MPG & DTE probably adjust within a mile of you being back in your lane)
• Miles per gallon you were getting
• Actual Fuel remaining
• Speed traveling

Suggest when you get low DTE to change to a conservative driving pattern, reset DTE, & you now might have better estimate of remaining range. Beyond zero DTE you have exceeded the margin for what Toyota could help you with.

The EV comments are interesting. Until solid-state batteries come along, the current EV batteries are as finicky as anything. External factors really come into play with EVs much more than gas vehicle. Work great in CA, not so optimal in Maine or Arizona.

Super cold weather kills range. You might park outside @ 40 degrees w/ 3 miles left DTE, stay overnight & wake up @ 12 degrees & the cold-sink effect on the battery is now @ negative battery voltage available. Same goes for high heat driving - especially slow speeds in city as road material - concrete versus blacktop - absorbs high radiant heat & transfers to the bottom of the vehicle(battery) & can steal range. The on board vehicle systems does its best to not let these factors hurt the battery, & that safety is @ expense of DTE. NiMH are decent in heat & cold (what’s in LC), where Li-ion are very susceptible to cold sink & runaway heat issues - but they hold much more energy for their size than NiMH.

Keep in mind that in cold climates, EVs use the battery (or heat pump driven by battery) to keep the battery at a nominal temperature while parked and "off". You can put them to sleep so this doesnt occur, but then you cant just jump in and take off. EVs dont work efficiently in cold climates with lithium packs as you say. Solid state is right around the corner, supposedly.

 

[GR8Santini]

Keep in mind that in cold climates, EVs use the battery (or heat pump driven by battery) to keep the battery at a nominal temperature while parked and "off". You can put them to sleep so this doesnt occur, but then you cant just jump in and take off. EVs dont work efficiently in cold climates with lithium packs as you say. Solid state is right around the corner, supposedly.

I asked my AI co-pilot Claude, he said battery heat circulation systems focus on preventing battery freeze damage, but cold ‘vampire’ range reduction is real. In Canadian cold-weather testing, their new Toyota bZ4X delivered 158 miles versus a posted estimate of around 252 miles — roughly a 37% shortfall - in frigid conditions, adding that below freezing EV vehicles may see more than 20-40% range loss. Looked like Tesla outperformed the other EVs. I’m interested in the technology, but just not a customer because of driving profile/lifestyle.

 

[Sugarloafer80]

As a 2 EV owner, I wasn't going after the temp and overnight parking scenario....I get it...garaged cars much less susceptible.... but when actually driving they are pretty darn accurate without all these variables regarding real volume/gallons we are discussing. Last 2 winters , my little Fiat that is garaged showed very little differnce. I think I went from ~126mpge to 115mpge..... that was before I learned new terminology.

 

[Sugarloafer80]

THEORETICALLY...

My understanding on the tank is that the well in the tank is intended to hold ~2.5G while parked on a level surface (to provide a thermal sink for the fuel pump). So 17.9-2.5=15.4. 15.4x20(say)=308 miles tank range as a sanity check. Therefore, Empty for DTE is at/near the 2.5 gallons from dry, the same spot as instrument fuel gauge zero. How much additional fuel can be pulled from the well is essentially a function of how level the vehicle is.

@Sugarloafer80, you get some outstanding economy and it seems you've got a repeatable trip, but you're right at the ragged edge in your scenario... traffic jam can only last 2 hours, not 2.5 sort of thing...

Edit: I've skipped the major variable - where is "1-click full"? How repeatable is 1-click full? Across pumps and vendors? Presumably, wherever perfect 1-click full is exactly 17.9G and any additional fuel genuinely extends range (and endangers vapor canister, etc) "Neck-full" is at least repeatable somewhat. What do pilots do for temperature influence on volume? ....they go by weight, don't they...

This would make sense. I have yet to be able to get much more than that in tank after 370miles and my mpg indicates and I typically confirm after fillup at 20.7-22,4 conditons being the variable. 17.87-16.5 gallons. Makes senses then that there is indeed a bit more to be added after the initial click....translation, she will hold~19+ gallons, this being the prime reason I can get the trip done non-stop. No I don't leave it parked that way, but i have no problems topping up morning of the trip with my track cans......

 

[Mopper]

There does seem to be a difference between neck-filling (if you will) and driving vs. neck-filling and parking

 

[DubDub]

There does seem to be a difference between neck-filling (if you will) and driving vs. neck-filling and parking

My wife neck filled her 2018 TRD Pro, without my knowledge, for the first 5k miles way back when. It resulted in a ton of limp mode scenarios and diagnostic visits to clear codes and try to figure it out. Fuel lines were replaced, entire cable assemblies were re-ran. Then they located a wire harness that we would have never known was cracked and susceptible to water ingress. After half a dozen trips to the dealer they finally asked about the gas cap, which led my wife to explain she’d never forget about the cap because she filled to where she could see the fuel surface… and I paid out of warranty repair to replace a pump and filter.

Long story short, there’s such a small gain to neck fill, but a massive liability in doing so.

 

[Mopper]

Ouch. That's not good, sorry.

My statement is based on an '02 Gen3 4Runner- I bought it used and it was immediately apparent after one night in the garage that the carbon canister was saturated. I did nothing about it other than parking outside and being certain not to get it too full. Some months after that, the rear axle seal blew and I had the vehicle back inside the garage. The gas smell was gone and I started parking in the garage again without issue (or smell). All good until I overfilled one day coming home from work and parked inside- the garage reeked of gas shortly after. The vehicle lost the smell after another several days outside and my usual commutes (say 60/day).

What I eventually decided from watching this behavior and neck-filling was that if you're going to drive 30 or 40 miles immediately after filling, go ahead and top off (the scent wouldn't appear). If you're not going to use enough gas to "get below" the carbon canister immediately, don't top off because you'll impregnate the carbon canister and things will stink.

I have no idea if this is correct, it was an empirical observation on a 25 year old model vehicle made 15 years back. The vehicle is long gone but I have a different Gen3 I still sometimes fill this way. I have also neck-filled my LC a couple times but typically avoid it other than the 3 or 4 instances. Neither vehicle seems to have shown ill effects and they're both garaged in a non-smelly garage daily right outside my back door.

 

[Sugarloafer80]

Right, never do that ...on track where it immediately gets burned is different than hydraulics pushing fluids everywhere till gravity levels off. That was my point a few months back. I have on several occasions seen 2+ gallons more go in WITHOUT being at neck after the 1st click. Just a slow fill till it clicks again..typically at stations that pump REAL fast...like my Costco. Every car is unique here. RR wouldn't take another qt.....Lotus due to flat tanks would take gallons.....I typically listen for the filler neck sound and stop. All good. Haven't run out yet....................................its like playing chicken with the gas gauge.
The ONLY time I ever ran out of gas was on my Tribeca back in ~2007 when I was hauling my Kayaks. it went from 50 miles??left to blank screen to DOA on side of highway in like 10 miles....Less than 5 from gas of course.......It was a dinky tank for a motor and tranny that weren't exactly efficent...Thinking 19mpg ?????? We have comne a long way in the past 20 years when our 5450lb LC does better.......

 

[cruiser_ss396]

you'll impregnate the carbon canister

if this happens and the gestation period for a carbon canister is known it could work out with getting a replacement new carbon canister as long as it can carry to the full term. Proper planning could keep a Land Cruiser in replacements indefinitely if timed appropriately .

Ok ya it was a stupid joke….

 

[Mopper]

Right, never do that ...on track where it immediately gets burned is different than hydraulics pushing fluids everywhere till gravity levels off. That was my point a few months back. I have on several occasions seen 2+ gallons more go in WITHOUT being at neck after the 1st click. Just a slow fill till it clicks again..typically at stations that pump REAL fast...like my Costco. Every car is unique here. RR wouldn't take another qt.....Lotus due to flat tanks would take gallons.....I typically listen for the filler neck sound and stop. All good. Haven't run out yet....................................its like playing chicken with the gas gauge.
The ONLY time I ever ran out of gas was on my Tribeca back in ~2007 when I was hauling my Kayaks. it went from 50 miles??left to blank screen to DOA on side of highway in like 10 miles....Less than 5 from gas of course.......It was a dinky tank for a motor and tranny that weren't exactly efficent...Thinking 19mpg ?????? We have comne a long way in the past 20 years when our 5450lb LC does better.......

It IS like playing chicken with the gas gauge!! Kinda fun in a High Noon sort of way.

if this happens and the gestation period for a carbon canister is known it could work out with getting a replacement new carbon canister as long as it can carry to the full term. Proper planning could keep a Land Cruiser in replacements indefinitely if timed appropriately .

Ok ya it was a stupid joke….

Sure do love jokes... !

 

[Sugarloafer80]

if this happens and the gestation period for a carbon canister is known it could work out with getting a replacement new carbon canister as long as it can carry to the full term. Proper planning could keep a Land Cruiser in replacements indefinitely if timed appropriately .

Ok ya it was a stupid joke….

I was so going there too!!!!!!!!!!!! His bad joke o meter went into labor before mine.............

 

[Sugarloafer80]

Maybe I drive up next Monday no-stop. When I get to house, run down to station with my extra tank and fill it. Leave in back and REALLY play the game...let's see if I can pull off 400 miles.......hmmm do I roof it, hitch it, rear cargo area it, or hold it with my hand out the window....hmmmmmm

 

[Mopper]

Gotta tell @cruiser_ss396 & @Sugarloafer80 .... it was only a little impregnated...

...there is no groan emoji, I already looked...

 

[MSINAL]

There's also the saying that "you're not lost until you run out of gas" For us tourists heading out west, we're likely to get lost at least once. Having extra gas is peace of mind. Just need to be pragmatic about it.

 

[Sugarloafer80]

It's very hilly where I'll be so one sputter and i stop. I will add the metered dose to get to station. Then I will do a complete just short of neck fill to put this to rest!!! And yes, on the level........ No downhill listing right special.

 

[Mopper]

It's very hilly where I'll be so one sputter and i stop. I will add the metered dose to get to station. Then I will do a complete just short of neck fill to put this to rest!!! And yes, on the level........ No downhill listing right special.

Careful- the heat is hard on the pump and the pump will progressively become less submerged before that last sputter... so be ready... or maybe not do it? I did kill an Explorer fuel pump AT THE PUMP... and thanks for taking one for the team and figuring out what capacity looks like if you decide to go ahead. And if it counts for anything, I think what killed the Explorer pump was cold fuel on a hot pump.

 

[Sugarloafer80]

I was thinking of that. If I make 400 miles I will call it a win..........400mi/22mpg=18.18 gallons...........that would let everyone know you truly have that to work with. 18 and dead is different than 18 and still going........if they advertise 17.9 gallons, I find it hard to believe that the last 2+ gallons could affect the longevity of a part...that could easily be turned into a class action event, false advertising! My gut tells me 17.9 usable and rest is that fuel pump well, but even a pump only runs hotter when WOT or hard/hilly accel etc....I would suspect. Hot pump in gas...not very wise.

 

[dobermancruiser]

I think if you're hauling fuel on the roof-
View attachment 74233
As I just did or considering it-

• 2x RotopaX 2nd Gen in the picture with a full width support plate. They are awesome. But even RotopaX says burp your containers if the temp changes more than 10F or altitude changes by 1K feet. I would consider well before either doing as I have or putting possibly less capable containers above your head.
• Wait to put fuel in until right before heading "out". Use all the fuel when you're coming "back". Or use it on the trail. Minimize hauling fuel at anything above, say 35 or with any appreciable traffic. And personally speaking, all the roof razzmatazz comes off as soon as I'm home anyway.
• @ultane got it right above, I think of it as "what's the worst that could happen". But if you chase that logic out is it really safe to put fuel on a hitch carrier? ...or next to the passenger windows? ...or on the roof?... @EOD Guy changed his tank likely somewhat due to these concerns

Edit: And @Area 51 likes it!

I asked Rotopax about this at the Overland Expo. I'm going to guess you have it secured with the clasps that go through the middle. I'm getting ready for a long trip at the end of the month and I'm trying to figure out if that's the route I want to take or just add a molle panel and hang it on the side.