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Discussion Starter #1
To remove as many variables as I could I fueled up at the same pump,
at the same time of day and the same fill rate no top off, early morning. Target speed was 65mph +-3mph, I was being past by most vehicles. This was on I 10 toward Tucson, it was +100 deg F, the AC ran the whole trip (blowing out 40 deg F air). The egt was 700 deg F +- 25 deg, boost was a constant 4-5 psi.
56 miles of in town driving and 218 mile on the interstate.
9.748 gallons were used. 28.108 mpg from my home in Mesa to Marana and back.
 

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Good job on eliminating the variables! Check your tire pressures for maximum recommended pressures and with a non aggressive tread pattern you should remain in the 28+ MPG range.
 

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Discussion Starter #3
Good job on eliminating the variables! Check your tire pressures for maximum recommended pressures and with a non aggressive tread pattern you should remain in the 28+ MPG range.
I'm stuck with BFG muds, but they were all inflated to 33psi cold that morning.
 

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HOT DAM. I hope my MINI cummins gets that. i think im going to do a waste gated turbo tho and some mods. i like the CUMMMMMMINS POWER. :dustin: :dustin:
 

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Discussion Starter #5 (Edited)
Controlled Test No. 2

Went camping in the Chiricahua mountains this weekend, that's a climb from 1200 ft to 5200 ft.
Fairly loaded with camping gear, but the Scout wasn't sagging.
The goal going up (south) was to maintain 65-70 mph, not sparing the throttle if needed. Weather went from mild to light rain. There was about 50 miles of construction 55 mph both ways.
Refueld at Sunizona at 216 miles, put in 9.708 gal
Scout got 22.38 mpg, good but not great.
The trip home went a little faster, 70-75 mph, traveled 260 miles to the fuel stop. Put in 13.244 gal.
Scout got 19.36 mpg, that's what you get when you operate in the power zone. Even thought the trip home was a gradual decent the extra speed ate up any chance of better mileage.
 

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That sounds more like it. It's one thing to talk about ideal circumstances, etc., but that's not really life, is it?

Nobody wants to get passed by going 60 mph. Most of us don't live on flat terrain, and many other variables.

It's nice to see what we "can" get, but it's also nice to know what we have to expect everytime we go to the pump.

I know my 23 average would probably approach 28 by staying off the power, and driving on flat ground, but that's a pretty big "if".

Thanks for sharing.
 

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To remove as many variables as I could I fueled up at the same pump...
One variable not taken into account is fuel expansion. To reduce the affect this has, one needs to run the tank down to almost empty or refuel with the fuel being nearly the same temp between vehicle tank and station tank. Any time one fills up a partially full tank that has fuel in it that is at a different temperature than what is being pumped, the mpg calculations will be skewed.

'Cold' fuel in the vehicle tank will result in lower mpg calculated than true and 'warm' fuel in the tank will give higher mpg calculated than true.

Thus pumping fuel out of an underground tank at roughly ~50 degree F(that's what it is around here atleast), driving around and then filling up a partially full tank will result in a higher mpg figure than what was actually attained.

Just one more reason why it's best to calculate mpg over several tankfulls.

That aside, that's great mpg!

Ken
 

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Discussion Starter #9

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I'm stuck with BFG muds, but they were all inflated to 33psi cold that morning.
Aren't all BFG muds D rated? Shouldn't they be around 50 PSI for best mileage? At 33 PSI I'm not sure I could keep my truck with BFG muds on the road.

I run 50 PSI in the 35X12.50R16.50 BFG muds on my 71 F-250 4x4. I bought the tires new in 2003 and they have approximately 85,000 miles on them between two trucks they've been on and still have between 30-40% tread left on them. Best damn tires I've ever had.
 

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Discussion Starter #11 (Edited)
Aren't all BFG muds D rated? Shouldn't they be around 50 PSI for best mileage? At 33 PSI I'm not sure I could keep my truck with BFG muds on the road.
cut....
Yes there are D rated. I had them at about 40 psi front and rear for this drive/test.
 

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Aren't all BFG muds D rated? Shouldn't they be around 50 PSI for best mileage? At 33 PSI I'm not sure I could keep my truck with BFG muds on the road.

I run 50 PSI in the 35X12.50R16.50 BFG muds on my 71 F-250 4x4. I bought the tires new in 2003 and they have approximately 85,000 miles on them between two trucks they've been on and still have between 30-40% tread left on them. Best damn tires I've ever had.
Probably not required in a light weight truck operating at less than half the rated load. They typically have a min rating which I think is around 30psi or so.

I have run my D's from 35-50psi in a truck that weights double the scout and saw no difference in mileage. I can not tell any difference at all in the performance of the tires at higher pressure. Since I started towing alot more I keep them at 50psi, but that is only to get max load rating with no issues.
 

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Discussion Starter #13
Update, 316 mile round trip from Mesa AZ to Safford AZ.
Used the same station/fuel pump/time of day for fuel stop.
Goal was 1900 rpm/65 mph average, AC used on the return trip.
Scout weights approximately 4900 lbs with driver and load.
New BFG MK2s inflated to 38 psi front/33 psi rear
This is a route that has lot of small hill and passes, some 7%.

25.75 mpg
$0.26 per mile
 

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You are Da-Man!

tires: 33x10.50r15 BFG MUD
gears: 3.73
trans: NV4500
For comparison sakes, I have a '71 Scout 800 with the same tires & gear ratio, 304 V8, T98 4 speed, weighing in at a portly 4,760 lbs.
My most exceptional fuel mileage was 19mpg... once. And I'm pretty sure there where angels pushing me along the path (or... more likely I screwed up the calculations :D)

My average, in town is 12 mpg, freeway at a steady 65 17 mpg, combined tank after tank, after tank, after tank, after tank... et nauseum over two years, is 15mpg.
I drive like an old man heading to his own funeral.
So... YOU ROCK! :beer:
I'm looking forward to my swap even more now. bounce
 

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Recently took a 240 mile trip mostly at 70mph. Hand calculated 23.4 mpg.

4bt non I/c with timing bump
47rh
3.55
30" tires
~6,000 lb dodge ram

EGTs were around 850, and rpm was calculated after the trip :)
 

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That sounds more like it. It's one thing to talk about ideal circumstances, etc., but that's not really life, is it?

Nobody wants to get passed by going 60 mph. Most of us don't live on flat terrain, and many other variables.

It's nice to see what we "can" get, but it's also nice to know what we have to expect everytime we go to the pump.

I know my 23 average would probably approach 28 by staying off the power, and driving on flat ground, but that's a pretty big "if".

Thanks for sharing.

I would agree. My best tank was 25.2MPG doing similar driving, but since I tend to cruise at 75MPH and do a lot of city driving, I always fall short of that and I never advertise that 25.2MPG figure as my "normal" fuel consumption.
 

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Discussion Starter #18 (Edited)
Trip over the mountains

For this trip I hit the highs and lows in Az.
Target speed 60 mph to 65 mph (1800-1900 rpm)
Scout (5000 lbs), towing the Casita (3000 lbs)
Started in Mesa AZ. (el 1200 ft), took US93/I40 to Kingman (el 3340 ft) down to Bullhead City (el 540 ft). There is a 12 mile 6% grade between Kingman and Bullhead City, a good test of the cooling system. Spent the night there, It was only 110F that day, AC worked great. On the way up the 12 mile grade had to use 4th, held it at 2200 rpm. From Kingman headed east on I40, south at Ashfork (el 5164 ft) south on SR 89 to Prescott (el 5355 ft) then up SR89a for a night on top of Mingus mountain (el 7500 ft). Continue on 89a, then SR260 to Camp Verde (el 3247) up 260 to south on Strawberry (el 5800 ft), Pine (el 5300 ft), Payson (el 5000 ft) then south on SR 87 and home (el 1200 ft).
661 miles.
36.1 gallons
18.31 mpg.
First leg fill up at Bullhead City 15.34 gal/18.9 mpg
Second fill up at Prescott, 11.2 gal/16.8 mpg
Fill up back home 9.62 gal/18.9 mpg
There were quite a few hills where I had to use 4 gear, held the tach at 2200 rpm.
There were 2 roads where I had to use 3 gear (2200 rpm), on 260 up to to Strawberry from Camp Verde and on 87 from Payson to Mesa, even though the drive is a loss of 4000 ft, there are a lot of hills to climb to get back down.
I'm very pleased for the mileage the Scout pulled.bounce
 

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Great info. Doing the around town mileage as I finally got the right speedo cable. Be in Prescott in a few weeks and doing half your loop but in my van. Jeff
 

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Have some exciting news! Still no I/C yet but- mileage has been awesome when te motor has had a chance to warm up. I've taken 2 small trips about an hour each way. I have Pics of my odometer readings and pump readings for proof too :)

I logged 27.5mpg going south from wilmont mn to spirit lake ia. And today from spirit lake ia to worthington mn, 29.25mpg!

These were both flat roads at 55-60mph tops and mostly interstate. Kinda surprised I wasnt shot lol!
 
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