Gas mileage on a new 8.1

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Our local dealer tells me everyone who buys a 8.1 complains about the fuel mileage. Any real numbers?
Al

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Believe I read 9.2 street 12ish highway.
~KJ says ffffu-KAAAA de en-vi-ron-ment~

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Gotta rant here for a sec......
DO PEOPLE NOT REALIZE THEY'RE BUYING A 500CID V8 GAS ENGINE? You don't know that milage is gonna SUCK with knowing that fact alone................
OK I'm done. Thanks.

fuel
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My 1972 307CUI got 8.9 average if I was really nice to 'err.
~TLGM
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I'v had mine just over a week. So far my overall average is 8.6 mpg. All driving so far has been slow rural & city roads, with most trips barely long enough for the engine to be completely warmed. My commute to work is only 6 miles.

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Buying a 3 or 4 ton vehicle with a 500+ cu in. engine and THAN asking about mileage or asking at all is nuts. It's BIG it's HEAVY and it's got a BIG HONKIN motor. They use gas and LOTS of it. ;-) Larry

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if u gotta ask, u should not be buying...i admit i bought a diesel halfway for its pulling power..ands halfway for fuel useage...but if u figure i keep the truck 5 yrs and 150,000 miles, i barely broke even on the extra cost for the duramamax engine....
--


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For the Ranters....Unless you are buying the vehicle, new or used this last year 03 with a GVWR over 6000 lbs and then inservicing the vehicle to your own company and electing to take a 50 % depreciation loss to the company profits and needed to budget for the additional ROI income of state, and federal gassoline taxes based upon last years average millage. But that might be just a guess, anyone else using the information for Taxes this year??
The 5.3 gets 16 Hwy and 14 City, but the truck is pulling a 4000 lb trailer about 75% of the time.
Hope that helps
Lee
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last
your own

profits
just
trailer
All I wanted was the mileage people are getting with the 8.1, didn't mean to start anything.
Al
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a friend has the 2500 crew cab 4*4 with the 8.1 gets somtihing like 10 mpg
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Elbert Clarke
elbert.clarke**@us.army.mil
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I get 12 or so with 5.7 3/4 ton long bed with 4.11 gears so the 8.1 is not doing bad and, a lot more power. Has anyone put a late 7.4 in place of a 5.7? What needs changed in a 96 model and a damned fine truck.
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REAL numbers on my 8.1L w/ 4.10 rear, 4WD, crew cab, long box: Averaging 8.2 MPG city/hwy Done as good as 10.0 MPG w/ more hwy than city Have yet to take an ALL hwy trip on a tank, but my Dad's '02 8.1L w/ 4.10 rear has done as good as 12.5 His towing a 32' TT w/ slide that is around 10K lbs. has been between 8 and 10 MPG I have yet to tow our 32' fifth-wheel w/ slide so can't give REAL numbers on my experience.
Like has been said here though, you don't buy 'em for economy! They like to drink! <<GRIN>>

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I'm not speaking for the other guy, but I asked about gas mileage on my 04TB because I was concerned about engine performance. (getting 12 mpg).
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had mind for 1 year ....
if you take it easy you will average about 11 in the city and 14 on the interstate ...
and to my suprize the type of gas does seem to matter ... i get the best mileage with shell and the worst with hess ...

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11 and 14!!!!!!! Is that figured using NEW math or achieved by shutting the engine off with a strong tailwind pushing down hill???
Even the 6.0 is lucky to get 12.5 - 13 MPG on the highway....... I know, I had a 6.0L w/ 4.10 and now have the 8.1L w/ 4.10. The 6.0L would do a solid 12.5 MPG and the 8.1L is lucky to get 8.5 - 9 MPG city/hwy. ALL highway it can get to 12 MPG.
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fuel
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depends if your talking the same body style truck.. I could believe 12.5 - 13 MPG from a 8.1L with a Reg cab long bed... That's what I got with my old 91 F250, w 5spd, & 4.11's Reg cab long bed..
That's close to what I currently get with my 2002 2500HD Silverado 6.0, 4.11, auto.. (13-14 highway) Reg cab long bed.
I would also believe 8.5-9 if the 8.1L was in a X or Crew cab... or a 3500HD .. It's the weight & final ratio that makes the most diff in the mileage for HD trucks.
my next one is going to be a 8.1L
JJ
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The 12.5 MPG was from an '02 2500HD w/ 6.0L, 4.10 rear, ext. cab, short box, 2WD
The 8.5 - 9.0 MPG city/hwy is from an '02 2500HD w/ 8.1L, 4.10 rear, Allison tranny, crew cab, long box, 4WD I have yet to run a large portion of a tank on the highway alone, but know of another ext. cab, long box, 2WD that gets around 12.5 MPG doing such trips.
Can't even imagine getting 14 MPG from the beast unloaded on the highway. It will be quite interesting to see what it does towing our 32' fifth-wheel this summer. The 6.0L averaged about 9.0 MPG doing that work.
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the
the
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I have the 3.73 rear ratio.. that could provide a small improvement in gas mileage
armond

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just drove from florida to west virginia during the holidays ... on the interstate mileage was between 13.4 - 14.4 for each tank.. speed was around 65-70 mph ...
in the city to get 10.5 to 11 mpg i found the key is to use cruise as much as possible
a.

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if stop and think 8 to12 isnt bad for the power
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