What the worst that can happen?

[4Beast]

i have definitely noticed that even when I'm at E and the trip info computer thinks that i only have another 20 miles or so, that i can usually only fill it 20 gallons or so (second click), which always seemed odd, as i believe it is a 25(ish) gallon tank. So either it's not representing the "lowness" or the "fullness" accurately. And btw, i never get 300 miles on a tank--with my V8 4Runner, yes, but not with this tank!

 

[2001LC]

The practice of topping off the tank has been debated many times. I'm amazed (but probably shouldn't be) by the number of folks who either don't read or don't believe their owner's manual where it very specifically says to not do that due to possible damage to the emission system. Parts for these trucks can get spendy; why risk long term damage for the sake of a few extra miles per tank?

This must be warning after 2001 (02). As I've read 98 & 01 OM's (LC & LX's) and have not seen anything other than "don't get fuel on paint." Did I miss something?

In my 2001 with charcoal canister up front:
I've been topping (double squeeze after auto shut off) for past ~13 years, 335 fill ups, 7,032.74 gallons of gas at a cost of $20,755.98 with average MPG of 15.11. With no ill effects nor have I ever broken down or had a CEL come on, and it still has the factory gas cap.

Again just one more reason I'm fond of the 01, the 50th year of production.

 

[2001LC]

***
Also, I have read (don't remember if here or on F transit forum) that the station pump systems have an auto return feature that routes overfilling back to the underground tank. Makes sense to me but I don't overfill so never see and overflow situation.

I too have read stores claiming they can get 30+ gallons reading on pump meter, in our 25 gallon tanks. They vapor recycle system in some states may be able to suck fuel back, IDK.

I do know I wait a few seconds after auto shut off to allow settling of fuel, then top slowly. I'm very purposeful in this and the angle of my rig while fueling. I' do this get as accurate MPG data that I can, which I've always manual calculated.

If that's too full then what is the correct fill level guys?

I think it's fine. If you run the pump on slow until it stops you're going to be like 2" below the filler. If AAron thinks another 3.6 gallons went in then I would say you've just been leaving it 3.5999 gallons too low. It can't be a 3 gallon difference. So many of these truck have slow fillers that I think relying on the pump shut off will give drastically different fill volumes.

I think if you stood there topping it off for a long time i.e. let it drop-top it off-let it drop-top it off-etc-etc then you will eventually fill the evap system with fuel and maybe cause an issue. If you just top it off and drive away then I don't see how you'll get much fuel into the evap system, that little column of fuel at the top of the filler should get burned off pretty quickly as you drive away.

Of course I have a '99 with the evaporator mounted up high and have never had any of the evaporator gurgling/vapor locking/fuel spraying adventures that many of you with later trucks have had. YMMV.

I agree that in the pre 03, a short drive get fuel out of filler neck with no issues at all. I've even parked in sun on hot day without any issues, nor have I had issue when ascending up mountain roads after topping.

 

[abuck99]

Since 2003 the charcoal canister was move to the rear near gas tank from the engine compartment. We've seen many story's of issues of vapor lock, gas smell & fuel leak when topping off with these. It's generally associated with ascending mountain roads right after topping off on hot days.

^ this

Altitude - high ambient temps- full tank- newer 100 series 03>

Doesn't seem to be much of an issue operating in lower elevations. But why bother filling it to the top of the neck? I could see it if fuel availability was 200 miles apart but here in the East there's a gas station with in a couple of miles from anywhere- it's not like you'll risk running out of fuel based on lack of access to fuel.

Especially based on the design and poor location of the canister by the spare tire, the fuel overflow and tank sits nearly parallel with the canister increasing the likelihood of saturating the canister as you overfill. It's a terrible design location, but we're stuck with it. From what understand, once you saturate the canister, it's pretty much toast. Spendy part too.

 

[Greenbean]

Why what happen to data?

The unit calculates my distance to empty and current MPG and trip info based on what I unput.

When I fill the tank I'm supposed to let it click off by itself then I enter the gallons filled and the current mileage.
And also price per gallon to track costs.

The more inputs the more the unit gets calibrated better and better. If I were to really fill it and go until I saw gas in the filler neck it would askew all I am trying to get dialed in.

No biggy but you better believe if/when I switch the Scan-Guage to another vehicle I'm going to really top of the LC and see what my tank can do. Hahaha

 

[2001LC]

Oh I see. I agree, consistence is the key to accurate reading.

 

[aaronrules]

If that's too full then what is the correct fill level guys?

I think it's fine. If you run the pump on slow until it stops you're going to be like 2" below the filler. If AAron thinks another 3.6 gallons went in then I would say you've just been leaving it 3.5999 gallons too low. It can't be a 3 gallon difference. So many of these truck have slow fillers that I think relying on the pump shut off will give drastically different fill volumes.



I think if you stood there topping it off for a long time i.e. let it drop-top it off-let it drop-top it off-etc-etc then you will eventually fill the evap system with fuel and maybe cause an issue. If you just top it off and drive away then I don't see how you'll get much fuel into the evap system, that little column of fuel at the top of the filler should get burned off pretty quickly as you drive away.

Of course I have a '99 with the evaporator mounted up high and have never had any of the evaporator gurgling/vapor locking/fuel spraying adventures that many of you with later trucks have had. YMMV.

I may have stood there and went very slow until it clicked...let it settle....then kept going until I literally saw gas in the gas hole.

Mine is 2006. I was VERY surprised the pump said I put 3.6ish more fuel in after first click. After roughly 12-15 miles put on since doing it, the needle is still visibly past the full line.

I have a scan gauge 2 that I need to figure out why it's not working correctly otherwise, I would be posting up my true mpgs.