Will some of you out there please post what gas MPG's you see for a 5.4, Auto Trans. with the following rearend ratios:3.73,3.55,3.31,3.08.
(I mean what you end up with after compensating for tire mods) I can figure in theory what the results of certain gear/tire/RPM combinations would be, but I would like to know what you people actually experiencing. I need to know what realistic expectations I should have.

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1999 F250LD Lariat s/c
Deep Wedgewood/Harvest Gold
Class III Tow pkg.
255/70/16 tires
5.4 v8
3.73LS rearend
Auto trans.
16,000 mi.




[This message has been edited by MJVAUGHAN (edited 08-08-2000).]

 

I am doing a fairly extensive test on MPG with my 98 Expedition 5.4 4X4 XLT(3.73, 17 inch) with and without the SuperChip. On and off road. City and Highway. Easy and hard driving. 93 and 87 Octane. Mobile, Texaco, etc... Distance, gallons, and MPG....

I was curious if the SuperChip does in fact "learn" and give "improved MPG."

I know one thing, I was getting 17-18 MPG highway consistantly on my first 5.4 (to 50K) and 14-15 with my FQR (8K)... Very big difference... Not sure why? I think my FQR is the 260 HP. It sure feels much more beefy than the original engine...

I can post my current data if you like. I am in the middle of the test and can only post data for about 8-10 tanks worth. Most of which has the Chip installed. I am now running 87 again without chip.

Up to ya'll??

 

Without any mods. Mine has averaged right at 15mpg on regular 87 octane. I have the 3.55 rear, 17"ers. I just installed an intake system, so after I play with this 1st tank, I'll let you know where I'm at. That is if I can patiently wait to install the Sweptside

Sven

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2000 F150 XLT 4X4 Off Road 5.4L Reg. Cab
K&N, WMS Velocity Tube, and Gibson Sweptside...

(For now)

 

What size tires are you using, so I can figure what the diameter would be.

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1999 F250LD Lariat s/c
Deep Wedgewood/Harvest Gold
Class III Tow pkg.
255/70/16 tires
5.4 v8
3.73LS rearend
Auto trans.
16,000 mi.

 

MPG avg = 15

Specs and mods which may influnce this are as
follows: 4.6L automatic supercab 4X2, 3.55 gears, Dual exhaust with 2 18" glasspacks, K&N filter, 265/75/16 All terrain tires.


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2000 F-150 XLT
4.6 Triton V8,3:55,AT,2WD
SuperCab, SB, StyleSide
Gold + Wedgewood Blue w/ tan interior, Captains chairs,
Mods:Kenwood 40x4 CD player/changer, True Dual exhaust w/ 18" glasspacks
w/ chrome tips out the back, bug/rock shield, K&N air filter,tinted windows
265/75/16 BF Goodrich All-Terrain TA's
Chrome Westin nerf bars.
Soon: Spray-in bedliner, maybe 3" spindle liftn eventually.




[This message has been edited by 19-SeventyFord (edited 08-08-2000).]

 

19-SeventyFord=Your effective gear ratio after changing to the larger tires is 3.38.
Thank you for the info.

 

mjvaughan,

I see you have a LD as well. After a few engine mods and larger tires, my gas mileage is 11.3 city and 12.4 hwy. Even with the engine upgrades and changing to synthetics and an overall tuneup, I didn't get any increase in mileage. And I even bought a soft tonneau cover. My truck just broke 20K miles. My truck did drop .5 mpg's when I changed from the 245/75 R16's. I do have a heavy foot so that counts for the lousy mileage, but it runs perfect and no complaints yet. Well except for the mileage :-(
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1999 F250 LD S/C XLT 4x4
5.4L, 3.73, 4R100 trans.
Flowmaster 40 series, K&N, Poweraid, Superchip, Rancho RSX shocks, Stull billet grille, 2-PIAA Pro80XT's (120W), 2-KC Daylighters (150W)
265/70 R17 BFG AT KO's on 17x8 American Racing Atlas rims
Kenwood 7000 CD, Alpine 3342 Signal Processor, Alpine MRV-F353 5Ch. Amp, Pioneer TS-A6865 3-way speakers, Lightning Audio 1 Farad Capacitor, RS10A Bazooka Bass Tube. CompuStar alarm/autostart.

[This message has been edited by Jupiterak (edited 08-08-2000).]

 

3.55 gears/ 5.4-auto. smoker(hope to have new engine soon) 6k

did just about 2000 miles recently on a trip and ave. 17.



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Dr.(wife says i'm spoiled) Jones.
2000 F-150 5.4L(whatpowerawaitsthee)
AUTO,SC-sb 4x4-XLT, 3.55LS, 8.8 front- 9.75 rear, sidesteps, sprayed in liner, 17"wheels ORP, trailer-tow pkg, CD, Cpt chairs, 4whl ABS, Keyless Entry, Airbox silencer removed/K&N, Amsoil(transfercase, motor, rearend), 3" custom dynomax ultra flow catback, as an anniversary gift. PSD coming for christmas!
djones01@elp.rr.com

 

I have been reading up, but what do you think about the superchip in regards to gas mileage? I have looked at some of the posts under chips, but I would like more numbers.
Thank you for your help.

------------------
1999 F250LD Lariat s/c
Deep Wedgewood/Harvest Gold
Class III Tow pkg.
255/70/16 tires
5.4 v8
3.73LS rearend
Auto trans.
16,000 mi.

 

I have 5.4 with the 3.55 rearend and 35"BFGs. I only get about 13mpg.

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2000 F150 XLT Supercab 5.4L
35" BFGs 16.5" Weld Outbacks
3" Fabtech suspension lift
3" body lift
Stull Billet grill

 

I am trying to get my gas mileage to the best possible within reason. I realize that my truck has quite a bit of power and will never be cheap to drive. Everyone on the boards is interested in improving torque/hp/power/perf. with little concern for MPG improvements. Am I just in the wrong forum for this these ?'s or what? With so many people experimenting with the different upgrades I just wanted to be smart & learn from you.

P.S.: I have learned quite a bit by the way!!

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1999 F250LD Lariat s/c
Deep Wedgewood/Harvest Gold
Class III Tow pkg.
255/70/16 tires
5.4 v8
3.73LS rearend
Auto trans.
16,000 mi.

 

I've been getting 15-16 mpg, about 60% highway which really matters! put in a Superchip 3 tanks ago and have not seen a change in mileage yet, have been carefull to drive the same so I could compare. is a 5.4l, 4x4, extcab long bed, 3.55l.

 

There are a few owners with Superchips that claim they get an increase in mileage. When I installed the chip there was NO increase in mileage and bad news is, I got pinging a couple times. Maybe bad gas?? Without the chip the truck has never pinged before. If you're trying to save $$ on mpg's; then I don't suggest you go out and buy a $200.00+ chip and pay more at the pump for premium gas.
I suggest first try a K&N filter, changing to synthetics/good tuneup and maybe a exhaust system. If you do get an increase in mpg; then try the chip.

------------------
1999 F250 LD S/C XLT 4x4
5.4L, 3.73, 4R100 trans.
Flowmaster 40 series, K&N, Poweraid, Superchip, Rancho RSX shocks, Stull billet grille, 2-PIAA Pro80XT's (120W), 2-KC Daylighters (150W)
265/70 R17 BFG AT KO's on 17x8 American Racing Atlas rims
Kenwood 7007 CD, Alpine 3342 Signal Processor, Alpine MRV-F353 5Ch. Amp, Pioneer TS-A6865 3-way speakers, Lightning Audio 1 Farad Capacitor, MTX Thunderforms. CompuStar alarm/autostart.

 

I don't think there is much you can do to the truck itself to get much better mileage. The #1 influence on mileage is the driver. High Speed (over 55mph), acceleration, hard braking that kills your momentum, all these are not taken into consideration when your EPA estimated MPG is figured. When I can take a #6000 truck that is supposed to get mid teens for fuel mileage and run the heck out of it and still get that I feal good!!!
Try running for a few tank fulls a little slower, coasting a little more before hitting brakes, not taching it so high on acceleration and you'll probably see quite a change, depending on how you now drive. Most people won't keep driving that way but it will give them an idea of what is possible and maybe find a "happy medium"
It would be nice to have a bolt on device that would double our mileage and HP at the same time, but guess I'm still buying that "winning" lottery ticket every week too.

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97 F150 4x4 SC 8' box, 5.4l auto 3.55LS.

[This message has been edited by Rob S (edited 08-18-2000).]

 

I have put on a K&N FIPK, and a cat back exhaust on my truck. It has helped the millage some, but not a huge amount.I used to get 15.5-16.0 mpg Now I get 16-17 mpg.
The other weekend I followed a buddy from NH to Cape Cod. This guy drives so slow, the fastest he did was 60 mph. I was amazed the difference in millage I got on that trip. I got 20mpg WOW never even got close to that before.
I allways drive between 65-80 on the highway depending on the traffic, I can't stand going slow, but was amazed that I could get millage like that.I know I will prob never get 20 mpg again, but maybee I can get a little better if I slow it down a little

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1999 F150 4x4 4.6V8 regcab/shortbed
Oxford White with Wedgewood Blue two tone, with Blue Captains chairs
Bullet Cat Back, Superchip, K&N FIPK Intake.
Centerline Saber rims 17x8" with Firestone GTA 275/60hr-17 tires.
Alpine CDA-7845, ADS P640 Amp, Focal Poly Kevlar seperates.






[This message has been edited by Don C (edited 08-18-2000).]