MPG with 35s

[OffTrac]

Ok, so I'm going to catch a lot of hell and disbelief and yada yada...but here goes.

I just checked my highway mpg on a single trip (small sample size). Filled up before leaving and at the same pump immediately upon returning. The highway has only a couple of lights and I only got caught at one, round trip. It's pretty hilly and got RPMs up to around 3k but for the most part stayed around 2k. Cruise control set at 60mph (according to GPS, speedometer reads 55). Temperature around 68* on the way there, low 60s and raining on the return.

Distance: 98.8 miles
Gas Used: 4.8 gallons

That's 20.5 mpg; the same hwy mpg I was getting with 32s.

I'm not using my odometer, btw. GPS, Bing and Google for miles traveled. I can only assume the pump was correct.

As for the gearing, 4.10s are sufficient. Unless you're used to driving an S2000, the gearing is fine. 4.56 would probably be better but I'm not going to be rushing to get new gears, at least not until I get locked. Take-offs now usually require 2,500 RPMs instead of the 2k I had gotten used to on 32s. Braking is more of an issue than anything. These tires seem to require more effort to stop than to get going, IMO.

Let the flaming begin. I know it doesn't make sense, but this is my one sample size so far.

 

[MidnightRebel07]

As you already know, your speedo and odometer are off so you can't go by either for an accurate reading. The cheapest remedy for this right now since you don't wanna regear would be to get an SCT XCal 3 Tuner and have Torrie tune it to recalibrate the comp. to the 35's.

For the braking, you know the steel wheels and bigger mud tires weigh ALOT more than the stock aluminum 16's and 32's. I'd do some searching around and see if bigger brakes from a Mustang would work or if they sell a four piston caliper you could bolt up to the Trac. Check out ExplorerExpress to see if they sell them. Actually, ask Torrie about this, they build some badass cars and trucks so he would know.

 

[OffTrac]

I will get the tuner, when the funds allow. It's been a modification I have wanted to do since I bought the truck and I now wish I had bought it much sooner. I've upped the hours I'm taking in grad school to try to finish faster, which carries an extra $1,000 each semester + books and extra gas... Wives are expensive, too (7 months in, lol).

I'm not as concerned about the brakes. They're good enough and most of the ST driving is around town, where the top speed is 40 (and I don't break the speed limit). I actually drive the Tahoe to class but my wife needed it today; I make 100 mile round trips 3x a week for class in the Tahoe, but put less than 200 miles a month on the ST. I'll replace the brakes as needed. I just keep in mind that the long term goal for this truck is a solid axle and I'm not going to dump a lot of money into upgrades that will be thrown away in the end. When I do replace parts, I'll go with upgrades, but not before necessary.

 

[OffTrac]

Turns out I am taking my Sport Trac to class again today; wife's going shopping for some clients all over the state. Except today, the location is different, there's more stops, less hilly; temperatures are going to be 10-15* cooler.

Distance is right at 95 miles round trip from driveway to gate (class is on an Air Force base). Got a full tank from last night except the drive from the gas station to home which is 2.7 miles. From gate to class building is unknown, but is short; we'll call it a mile in and out of the base. So, 98.7 miles. Funny how close that is.

I'll update with the MPG tonight. I'll be using the same pump again (non-ethanol, of course!). Now, to get some studying about public finance and budgeting done.

 

[ramren16]

a good brake upgrade that is cheap would have to be stainless steel break lines, they wound expand when breaking like the rubber ones do since you are having to apply more pedel to stop. at least that is my problem on 35s. you will never get a close to accurate mph reading that way, for one your tires are 6 sized bigger that stock thus traveling farther than car thinks(also effecting maintenance intervals, early)second you have to fill up vehicle reset trip meter, drive it till empty then fill up again and then look at how much gas you put in. miles on trip meter divided by gallons refilled with= mpg. other ways dont work

 

[OffTrac]

Thanks, but I'm not using the odometer at all. I know the short trips aren't ideal, but it's gives me an estimate. I don't drive this enough to be patient to wait for the next refill, so these are my "estimates." Waiting until I'm at empty would be nearly a month. Besides, I'm not going to track every mile I drive on paper throughout a month because my odometer isn't correct. This is the best I got to work with.

Today was a little closer to highway/city driving but still was 80% highway. The miles traveled may be a little more than shown above because I saw a bbq place that needed to lose some brisket and brunswick stew. It was probably a little more than a mile, but to remain conservative, I'll stick with the number I posted before.

Filled up again tonight upon returning at the same pump. Temperatures are not the same, about 15* cooler tonight, but I'm not shooting for perfection here.

98.7 miles
6.2 gallons to refill

15.9 mpg

That's still a little inflated because it was still mostly highway, but there was a lot more red lights (and I seemed to catch them all today), bendy backroads (haven't replaced the sway bar) and the hills were bigger and more frequent than I remembered. Still averaged around 60 mph.

Almost all of my daily driving in the ST is city driving (if that's what you call this small town I live in) and has a top speed of 45 mph. Stop signs and redlights abound. I'm thinking realistically, I'm getting around 12-13 mpg and I ain't complainin'. I'd have bought an econobox if I couldn't afford to fill up a "gas guzzler" once a month. I'm on 35s and doing about the same as my wife's Z71 Tahoe on 33s. Her lead foot is more costly, though.

I'll look into the stainless lines, but I know I'll do it when I go solid. I'll just see how it goes. Hasn't scared me, yet.

 

[Karpiel73]

I think you'd have to do a longer trip to get more accurate mpg's. I have an entire book of every fill up I have ever done since I bought my Ex in 2007. It just seems more accurate if it gets run almost dry then fill it up.

But if that's what you're getting then that's awesome!

 

[OffTrac]

I know it's not real accurate but if it's off by 5 mpg, that's still acceptable to me. I'm still only visiting the gas station twice a month and neither fill up is at a completely empty tank. As long as I can afford it, I don't truly care what the number is. I no longer take my truck on the highway drives except maybe 4 times a month so it's all city driving and mostly under 10 miles a day. My wifes Z71 Tahoe on 33s is doing worse than me, so I'm cool with that.

When I ran these (inaccurate) tests, the tires were at 40 psi because of the highway driving. I have since lowered them to a more reasonable and more wear-friendly 32. that with short, city driving, the mileage will obviously have suffered.

Another thing worth mentioning is that I only run non-ethanol gas. It makes more of a difference than people think.

I don't really care about gas mileage , though.

 

[sport97]

.

I don't really care about gas mileage , though.

If you did you wouldn't have gotten 35's!

 

[OffTrac]

If you did you wouldn't have gotten 35's!

Exactly!

I feel like some people (not necessarily on this forum) think I might be trying to lie about my gas mileage for some reason. I really don't care enough to bother. I just wanted to report my (although imperfect) results.

Take them as you will. I'm happy with my gas mileage because I don't really feel a need to give it much consideration. The day that the gas I put in my vehicles breaks my checking account, I'll have more life assessments to do than the gas mileage of my vehicle. JMO

And seriously people, run non-ethanol if you can find it.

 

[Karpiel73]

Quick question, call me a noob or what not but: What station has non-ethanol gasoline?

 

[LONO100]

i believe it, when my ST was still stock i was hypermiling with it, and i was able to get close to 27.5 MPG! once i got my little commuter car, i modded my ST out and now its my weekend toy. im still hypermiling in my commuter car and saving tons of money.

 

[OffTrac]

Quick question, call me a noob or what not but: What station has non-ethanol gasoline?

All three of the ones around me are small private gas stations.

 

[MidnightRebel07]

You're in the south, even summer blend gas in the north has atleast 10% ethanol in it.

 

[OffTrac]

So, it's not available in the north at all? Most stations only carry 10%E but a few stations seem to try to provide non-ethanol. They're having to charge more because they're getting squeezed and it's getting harder for them to get it. The one I get it from has 4 pumps and all 4 were non-ethanol until February when they had to go to 2 pumps with, 2 pumps without.

Filled up at $3.97/gallon today.

 

[Karpiel73]

Man that sucks to hear. I'd love to try out non-ethanol gasoline. I'll keep my eye out for non-eth here in Charleston

 

[01STrunner]

Non ethanol is really hard to find, even in VA. There's one station down near Clemson but I don't even know of any others around here in SC. It makes a huge difference in mileage. At least 2 or 3 mpgs on a tank. In my Monte Carlo I'm pushing 33 mpg. With part ethanol i get 26/27. In my trac I'm getting about 16 to 17 with 4.10 gears. And that's mostly highway driving.

 

[Karpiel73]

Found a 100% petrol station here in Charleston and filled up today. I called ahead and the lady said it was 3.69, only to get there and see it was 4.19! I filled it up anyway, $76.00 total. I'm excited to see the mpg's because I disconnected the ac compressor and took the roof rack off last night.

 

[OffTrac]

Cool. Let us know your impression of the results.

 

[Karpiel73]

I tried non-ethanol gasoline with this last tank of gas. The AC compressor was unplugged and the roof rack was removed (the ex gains 3.5 mpg highway just by removing the rack) for the trip to Savannah. About 90 miles was city driving. The highway driving did not go above 67 mph (cruise control). So here's the results for this:

351.7 miles on the tank (most i've ever got)
16.309 gallons to fill it up (still had ALOT left in it)
21.57 mpg's (best mpg's to date! 20.8 was best prior to this)

I had a gain in the mid-range power without a doubt. But I contribute no large gain in mpg's because of the 90 miles in the city.

So would I do use non-ethy again? Yes-minus the city driving of course!
The extra .50/gal did hurt though!