I don’t know if it’s common. It is/was common in my VW’s and Volvos. My MB really means it, so I can only top it up to the nearest dollar.
I do wonder if I’m ripping off the next person when I do that, but it’s not much gas, I’m not doing as you said and pushing the siphon along.
I mostly do it to avoid dripping gas down the side of my car when I pull out the nozzle.
Sorry to pile on but that’s pretty ridiculous as stated. I haven’t paid cash for gasoline in decades and have never in that time been left entirely high and dry due to problems with both credit cards I carry plus my debit card, or the pumps. And even then I do have cash on me, but I still wouldn’t go through the definitely non-sensible ritual of topping off. I’d just get change that one time every many years nothing but cash would work at a gas station.
Nor have I paid interest on a credit card balance, ever, using credit cards as much as possible for the cash back and the float.
The only rational reason to use cash at gas stations is if there’s a price for cash lower than credit price by more than cashback. With the main card I used for gas giving 5% cashback that’s never been true where I get gas. Or I guess exceptional cases where a person can justify the privacy advantage (in terms of someone tracking the card) in a non-paranoid way.
The reference to the link is the classic fallacy of using average statistics for something where you can make the personal choice not to be like the average. Nobody puts a gun to anybody’s head to run a credit card balance, and I never ever do.
I would think one good reason for topping off is so that you can make an accurate mileage calculation. I let mine run until the first click off for that same reason. Some cars don’t click off in the same place every time.
I don’t top off, and I mostly use cash for gasoline. I put $40 in the stash can every time one of us gets paid. Shell gives me three cents off per gallon for cash.
I did try topping off once with my new Forester, and got 1.25% more gasoline into the tank. It hardly gives an improvement in the frequency of stopping to fill up, and might damage the emissions control system (or so they say, but I’ve read that actually means saturating a carbon filter, and in my car that filter is up in one of the rear roof pillars above the fuel receptacle so I don’t think that could happen).
I have had a couple of cars that simply wouldn’t let me fill the tank (approach manufacturer-stated capacity) without going through filling, shaking the car and jostling the bumper, and then pumping in the last two gallons. The worst offender was a 1983 Datsun Nissan Sentra Diesel, so those two gallons meant an extra 100 miles range when I was on the highway. The reasons this car acted this way was a combination of diesel fuel foaming and a sharp curve in the fuel filler neck. The car had no emission control stuff since diesels were exempt back then.
When I do top off, it feels like a reflexive holdover from the Carter administration, putting as much gas into the tank as I could get because I didn’t know for sure when I’d be allowed to buy gas again.
This sensible person has two credit cards that are only used for gasoline purchases. I get a discount per gallon for using them. I drive a Corolla so a tank of gas lasts me a long time. I get an email every time the card is used and i pay off the balance every month.
I will let go to the first clickoff, then give it one more, sometimes that first one is premature. Though sometimes I can hear the fill up, the tone changes of the fluid flowing in the tank, if that is heard then I’ll let it just click off the first time. Beyond that rarely, however…
I had a car with something like a 16 gal tank, if I could go slowly at the end I was able to get 19 gallons in it, probably it had a non-CEL damaged vapor return system and a destroyed charcoal canister. I didn’t have to click, click, click it, but just go slow. Those extra gallons meant I only had to fill up every 3rd day of driving for work, instead of 2 days and it was nice to just go straight home, and stopping in the morning was an equally unpleasant option.
I do have to say that those clickers/thumpers are somewhat annoying when that pressure pulse is also felt in the pump one is using.
I have seen some unfortunates go through that ritual but not in a couple years. It would be understandable and obvious from watching that they’re not squeezing in a half-gill so they can get their credit charge to be a magical $25.00 flat or maybe brag, “I got 32.48264 miles per gallon!” instead of a mere 32.47863, forgetting that no matter what their calculator tells them their accuracy is only three or four significant figures anyway.
I swipe their fuel rewards for a nickel/gallon off the top. On Tuesdays this past winter it was bumped to a dime per. Then I pay with scrip purchased from school which gives the school 5-10% cash back depending on current incentive. My school applies that to my kids’ school fees account, such as field trips, book fees, tuition. I know of one extended family that had several kids’ fees paid by one family member who was an independent cross country trucker. He did all his trips via the scrip cards.
as far as topping off, my truck will kick out 3 seconds into the fill if the nozzle is on high. It only fills on medium. Over 1/2 - 3/4 gallon fits after the pump stops the first time. My Saturn not so much. It stops when it is all the way full.
Nope. I fill until the shut-off. I then keep pumping. I can usually get nearly a full gallon more into the tank, but I will stop pumping on a round number. Is it absolutely 100% full? Well, it’s not overflowing the fill pipe, but it’s more gas than the pump thought I should have, so…close enough for me.
I think it’s a little OCD, I like to top off to the nearest 10 cents, or at least 5. If I pumped $10.71 I’d go up to $10.75. Don’t judge me, and 4 cents worth of gas isn’t going to hurt anything. I guess it’s partly a game to see if I can get the pump to stop right on a multiple of 5 or 10 cents.
I try to take it to the next dime or quarter fraction if paying in cash just for the sake of easier change-making. If using the credit card I sometimes stop at the first shutoff, others I take it to the second, depending in the day’s mood — I do stop at the first shutoff when getting ready to return a rental car, as why give them back more fuel than they gave me.
Odd how many people here still top off even tho the manufacturers and the experts say not too. 
I’m not sure we have a working definition of “top off.” Some people are adding a gallon or so, clearly more than a top off. Some people are adding $0.04 worth, probably less than a top off.
Not really 
for me. I happen to know deep in my heart that if I can’t get either the gallon total or the dollar total to end up at a nice, round exact number, life as we know it will cease to exist.:eek:
You sound like my husband. He does this to an even more OCD extent than you’re describing. He still has Excel spreadsheets analyzing fuel data for cars we haven’t had in years.
I have it in one spreadsheet, but yeah every fill up for cars I don’t even have anymore. 
However I still don’t buy TCMF-2L’s logic about topping up wrt to tracking mileage. Filling the tank to the same exact level each time would be a necessarily condition for the calculated mileage on each tank to be exactly comparable. But it wouldn’t be a sufficient condition since the driving conditions also vary on each tank (what % ‘city’ or ‘highway’ often does, or even if all ‘highway’ the temperature, how hilly, delays for construction etc). Whereas the overall calculated mpg under your overall driving conditions is as accurate as the odometer and gas station pumps are over a series of tanks without any topping up. The small variations from tank to tank due to the pump clicking off at slightly different amounts averages out to zero in the long run.
I also highly doubt 2 gallon differences if there’s nothing wrong with car or pump.