Fuel Gauge Question

Saw this posted on Reddit and now I think I'm not crazy. Since I've owned my 24 (1yr) my computer has never showed over 287 mi to tank on the computer. Others are getting 350-380 to a tank before the fuel light comes on. Mine has never made it over 300mi on a tank ever. I've filled it from the fuel light being on many times, and I've never taken more than 19gal (and barely 19 at that). That leaves 5 gallons in the tank when the light comes on - and even going off my lifetime computer average, that's another 70+ mi. Does this seem odd to anyone else? My Raptor was far more accurate fuel wise.

Before anyone asks - I run at 71mph per the speedo which is 70 per GPS - getting roughly 18-20mpg by the computer.

 

Watching.

 

The most I’ve ever put in was 18.7ish gallons so that number you’re getting isn’t crazy, there’s a reserve capacity we aren’t usually supposed to touch and is pretty common in other vehicles, not this this one, or even Toyotas.

Buuuut since you’re not getting 300 miles per 19 gallons (15.7 MPG), something might be wrong. Does the vehicle coast as you expect? Tire pressures? etc.

 

Tire pressures are fine - 34 all around in the winter (they jump up way more in the summer). No mods, no suspension changes, lifetime MPG is 14.0 per the computer (and I am guilty of idling a lot). Highway MPG has gone down since I bought it, but never used the E brake, no stuck calipers, good alignment, nothing on the roof rack. GPS 70 on the Highway (hilly in Northern MA) is 18-19.5ish, if I jump up to 75 GPS it drops to mid 16s. If I can cruise around at 40-55 it's in the low 20s.

 

How much do you idle? I've averaged 15-17 since adding weight, lift, and tires (and lots of short drives) but my wife started it up and let it idle while clearing snow and I idled a lot on a trip to the dump on the last tank. The 'puter was showing 13.8 when I filled up yesterday. It was also really freaking cold here for a couple of weeks - not sure if temp itself had a hand in it. I think idling in these things can kill the MPG. I first noticed this on the wife's JGC when we started using the remote start to warm it up before each drive - it tanked the fuel economy

 

Oh she definitely gets idle time - depending on weather depends how long. When I'm clearing snow and ice, she idles. If I'm all clear and just heading to work I'll start it maybe 3-5min before I leave. Idle while I get coffee most days. It's been really cold here, and this tank is at 10mpg from idling- so that's expected. Biggest issue is my commute - less than 3mi round trip. Probably the worst town there is for MPG - 20mph speed limit, tons of stop signs, lights and hills. Still - seems a bit low. I take 200-400mi trips often, and it hasn't gotten any better.

 

Ah, that's your problem. How you drive it.

1) Idling kills MPG's.
2) City driving also kills MPG's.
3) Driving in hilly area's also kill MPG's.

Basically you need to ignore the "Current MPG" and look at the "Tank MPG". That'll give you a much more accurate read out and real time MPG. It sounds like you're averaging 15 - 16MPG.

Oh, one more thing. When the gas light comes on you have roughly 1 gallon of gas until the readout reads "0 miles to empty". After you hit 0 miles, you have 2-ish gallons still in the tank. Call it a reserve.

Trust me, I tested this once. I drove another 38 or so miles after the read out was 0. I even posted about it in a thread, and got roasted for it.

 

Why are we discussing someone’s post from Reddit who won’t even read the answers here? I know, it’s Sunday.

 

I read a similar experience on Reddit to mine, on a 24 Pro, so I figured I would post my question and experience here. I don't post on Reddit. I've read every MPG thread on this site - just seemed like too much of a coincidence that someone is having the exact same experience I am. I've never cracked 300mi on a tank, even driving from MA to Maine with zero idling and 70mph the whole way. Left the pump and the fuel light was on well before 300mi.

 

It takes a few thousands miles to break in everything. It can improve after 10k miles. Is it full stock?

 

Damn! Something must be wrong. I easily get over 400 miles to the tank, but 99% of my driving is highway miles. No sitting idle, no hills, no stop-n-go (well, not much).

 

Just under 8100mi at the moment. Completely stock.

New England is full of hills and shitty traffic.

 

I think that miles to empty measured on average from the moment you bought your vehicle. So one trip doesn't change value too much. I'm sure that if you disconnect battery long enough to reset system you'll see around 375 miles to empty. But then it will be decreasing according your driving, i.e. short city trips, winter idling, hills, high speed on highways etc. Also % ethanol in gas plays role too I guess.

 

Are you measuring it with by the odometer? E.g filing it up at 8,000 miles and you’re empty at 8,300 miles or just relying on the trip computer?

 

Well that would explain things. I guess I never thought of that because no vehicle I've ever owned operated like that - miles to empty was always based on the previous tank, not lifetime. My Raptor would regularly say 600+ after a road trip, but would fall under 400 if I spent a tank romping on it. I can honestly say out of my 2 wrangler, 2 grand Cherokees, S6, C63, Raptor, A4 - none of them based it on lifetime. Strange, but understandable.

 

Odometer. The fuel gauge drops right in line with the trash milage on the EVIC. Never get over 300mi no matter what.

 

Something is not right. This was my Friday afternoon NYC traffic average. I have a 2023 SR5P full stock.

 

Running up in the mountains (2500' to over 6000' ASL), +400 lbs, stock size ATs, upgraded roof rack with recovery boards (I found out they actually help airflow and MPG) I get 9 MPG going up, 25 MPG going down...yup the average pretty much aligns with both my Odo and tank MPGs at 17-18 MPG overall. On flat ground going across the Central Valley it almost hits 18/19 MPG average. Never saw 300 miles to a tank even with factory tires.