Just wondered how many miles people get to a full tank of fuel. My range is indicating 359 miles and I know it's a rough estimate depending on how you drive.

 

I think its a subjective answer. Alot I believe depends on your driving style (agressive / sporty / sunday drive...) I also believe actual mileage is impacted by type of fuel (premium, regular, supreme) tire pressure, routine maintenance etc etc...

On mine (03 STR) I tend to rack up mostly highway miles on slight rolling hill terrain (Ohio, Kentucky, Indiana) that said here is what I can tell you:

Tire pressure
32 Front tires
34 Rear Tires

Maintenance
Mobile 1 Full Synthetic (High Mileage) Oil every 7500 miles
Transmission Service every 50,000 miles (dont belive the sealed for life BS)
Radiator Flush and Fill every 50,000 miles
Brake fluid flush and fill every 50,000 miles
Differential flush and fill every 50,000 miles

Fuel
Only Shell, Mobile or Exxon 93 Octane Supreme Unleaded
Lucas Fuel System Cleaner EVERY OIL CHANGE SINCE NEW

All that said my average DTE (Distance to Empty) on a full tank is about 350 miles or 22 MPG

 

I just filled up my tank today (I never let my tank fall below 1/2 tank) I ran outside and checked - my needle is slightly below full - I logged 36 miles from fill up (highway)

My 2000 S Type - 4.0 V8

Tire pressure
32 Front tires
34 Rear Tires

Maintenance
Mobile 1 Full Synthetic (Extended Protection - good for 15K miles) Oil every 10,000 miles
Transmission Service every 20,000 miles or 2 years - recently rebuilt (I don't belive the sealed for life BS either!)
Radiator Flush and Fill every 75,000 miles
Brake fluid flush and fill every 75,000 miles
Differential flush and fill every 75,000 miles

Fuel
I live by Costco Kirkland 93 Octane Unleaded
Chevron Techron Additive - Every 3rd tankful (about every 1,000 miles)

As of tonight my DTE is showing 333 miles + 36 driven since fill up = 369 miles (22.4 MPG - avg)

 

When inquiring of fuel economy, please consider that different fuel tanks are "full" at different volumes. And different gas station pumps will put a different volume into the tank before automatically shutting off.

With that all in mind, fuel economy is best expressed in miles per gallon, or liters per 100km, or some sort of volume unit and distance unit ratio.

And with that in mind, I get a fairly consistent 22 mpg (US) combined and 31 mpg (US) highway. That's 2000 rpm on flat interstate. About 68 mph. I have a V6.

 

I get about 30mpg on the highway and 22mpg in the city. I also have a v6.

 

Thanks guys.

 

Yesterday I experimented with this on an 80 mile highway drive with relatively light traffic (for NYC metro area). I watched the computer's calculated avg MPG the whole way back. It's reasonably close to actual measured gas consumed so I'm OK with that.

Boy is it hard to keep that average up. This was a two way trip, 80 miles out and 80 miles back. So normal driving style on the way out yielded 19.5 gallons. That was with no aggressive driving but the usual lane changes and traffic maneuvers so yes that uses more gas than driving in a very sedate manner.

On the way back I really feather footed it and at the end of the day I got about 22 mpg but as soon as I got off the hi-way and drove 3 miles to my house it dropped to 21.6. That surprised me but then it's a pig around town.

The best I can ever do is in the low 22 range and that's on an open road. I don't see how anyone does much better than that with an STR? My car is in great shape too with only 32K miles.

 

I find it's VERY sensitive to road gradient (slope). I'm not really too upset as it gets "good enough" mpg. It's about 2 tons and high performance. It's a bit better mpg than I expected, actually, but mpg is not the reason I bought it

 

As noted above, it depends on how you are driving. Typically in town I'll see a range of 300-350 miles to empty. When doing strictly highway driving I'll see about 450 miles to empty. This equates to about 22 mpg in town, 32 mpg highway plus or minus.

 

That really is way better than my 2001 Sable with a very similar 24V V6 engine in it. I never saw 32 in that on the hi-way and it weighs no more than the Jag S-type.

Was Jag that much better than Ford in getting mileage?

 

Absolutely but it's also very sensitive to throttle. Even if you're not giving it enough more throttle to feel a significant improvement in performance it still sucks the gas a lot more. So even slightly more throttle than feather footing it yields a huge drop in mpg. That sounds like a very inefficient map is being utilized to mask any potentially damaging lean conditions which is great for engine protection but not so great when you're trying to be efficient.

But it's the sport model ...

Almost ten years later they're doing a better job of this but at over 500HP OMG! who can expect decent mileage. I'll bet the new 400HP V8 does much better than the old V8 SC one.

Too bad the new car is no where as nice looking on the outside ...

 

The really new engines improve mpg using:
1. direct fuel injection
2. stratified charge
3. cylinder shutdown (as an approximation, think of a V8 on low load being a V4)

Our cars don't do these

 

My commute is about 13-15 miles everyday in heavy traffic. It takes me 20-25 minutes to work and on average 45 minutes home on a good day. It's pretty much mostly beltway traffic or back roads with lots of stop lights.

City mileage: 15-17 mpg. I probably accelerate hard at least 2 to 3 times a day.
Highway if I go on a trip: typically 25-28 mpg
Tank typically will give me 310-340 miles.
My average speed is about 25 mph. LOL.. Range of speed is sitting in traffic idling and up to 85 mph, when I can open it up for a short 1/2 mile or so.

Same car as yours. 2002 4.0

 

I have a 2003 non-R V8. I use regular dino oil (whatever's cheapest at Walmart), change it at 10,000 miles if I remember, at 87000 miles have never changed the transmission fluid and use 87 octane or 89 if I'm feeling flush. Additives of any type are not permitted on my property.

Present fuel consumption figures over a 5000 miles average is 24.7 mpg (US gallons).

If I don't see 33-34 mpg on the highway I check tire pressures.

 

Wow the STR's map sure does exact a price.

 

Do you guys have ethanol blended into your gas?

 

Is that also US gallons?

If so, that would be just either side of 40mpg (British Imperial) or 7.13 liters/100 km.

Just hit the km/m button on the cluster to get the metric reading because that is unambiguous.

 

I don't believe the STR maps are a problem. It's a lower compression (than the NA) engine with more waste (the SC & intercoolers for a start).

I use cruise control a lot. Works for me.

 

Yes, 10%, we've had 'gasahol' for at least 20 years here.


Yes, US gallons. To my surprise, the car calculates using US gallons even though this was never a legal unit of measure in Canada. Although I set the car to display in Km and L/100Km I posted gallons and miles above to not confuse our metrically challenged neighbours to the south.

 

The 32 mpg was at around 72 mph (just below the state trooper speeder threshold). When I kept to 60 mph I saw 35 mpg. I didn't do this very long though. It could be a function of gearing or maybe the Jag drivetrain is more efficient than the FWD setup in the Sable.