35-37 mpg loss??

J-Mo · 06-04-2008, 07:03 PM

Im trying to decide between running 35s and 37s in a Toyo open country m/t. Im averaging about 20 mpg(hand calced) now. Im curious what the mpg loss would be with 35X12.50 or 37.13.50 if the difference between the two isn't that much id rather run the 37s

thanks, J-Mo

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Black 08 6.7 QC auto 4x4 sport, AFE stage2, PDI 5" TBE 6" tip, Edge Jucie/att./hot, mp-8, egr delete, 4.5 fabtech, dual bilstiens, thuren trackbar, fox stabilizer, 35"toyo mt's, 20" black rockstars, tint, bed cover, srt hood.....more on the way

Luvnacummins · 06-04-2008, 07:55 PM

cruising down the freeway mine went up because it dropped my rpms!!:thumbsup

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KBCummins5.9 · 06-04-2008, 07:58 PM

Im running 37's and geting anywhere from 14-16 in town/ hwy about 18-20

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2004 ram 3500 laramie, 4% tint, 6" superlift, 37/14in tires, Superlifts TruSpeed, 3500w amp twin 1800w subs, Banks six-gun & speed loader, Banks High-Ram intake, Banks Ram-air intake system, FASS fuel system, Aero exhaust, Exhaust break, Chrome Package.

1BadOilBurnerN-Lv · 06-04-2008, 08:06 PM

35's for in town 37's highway . I had 35's i got about 16-17 in town
, highway was only about 17-18 , Once i got my 37's i checked it 18.5 in town 21-23 highway . That was after my programmer and speedo recalibration . All was hand calculated :thumbsup

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2000 2500 sport extended cab short box , 5-speed. 6 inch miter cut stacks , silencer ring M.I.A. , B.H.A.F. 355 gears , 6 inch long arm rcd lift and 37's SuperChips , fass pump

TacSat1 · 06-04-2008, 08:15 PM

with 35"/37"s you speedo will read 65, in actuality you are moving at 70-72, which is in the sweet spot of 1600 - 1800 RPMS.

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2003 Dodge 2500, S.O., 48RE, 4x4, QC/LB, ISSPRO EGT, Boost, Trans Temp Gauges, Airaid MXP intake and 4" MBRP exhaust, Smarty on #5, Amsoil in the engine and a Transgo Shift kit

smkstk · 06-04-2008, 08:29 PM

bigger tire bigger mass, more mass more power to get moving, so like stated above, smaller tires for more town driving, bigger tires for more highway driving.

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Luvnacummins · 06-05-2008, 01:50 AM

on my truck according to my gps the speedo was off 13 mph!!!

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antwan718 · 06-05-2008, 01:53 AM

Quote:

Originally Posted by Luvnacummins

on my truck according to my gps the speedo was off 13 mph!!!

How fast were you going that it was off though???? Either way thats a huge gap.

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-03' 5.9L w/Edge Mileage Max, 4" TBE, GHD, Modular Intake, Boost elbow
-85" Mustang GT CFI
-70" 440+6 Challenger R/T

terminaltsi · 06-05-2008, 10:43 AM

the faster you go, the more the speedo will be off.

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'99 2500 5 speed, 4x4, gauges,Quadzilla ADR, Smarty, BHAF, 5" turboback, 315/75/16 maxxis bighorns, Airdog, 13" Valair,3000k HID's, HID off road spotlights, LED back up lights, LED interior lights,alpine/cerwin-vega/mmats audio.

dieselrambud · 06-08-2008, 07:01 PM

With 37s my speedo is off 14.5%. Best I have ever got w/stock tires is 16mpg highway. Yesterday got 14 mpg highway w/ 37s. All hand calculated.

__________________
2008 2500HD, 4x4, megacab, 6-auto, Rize 8" lift, 37"x12.5" Pro Comp Xtreme ATs, Dick Cepek 17x9, 35% front tint, Bilstein 5100s-Wife's truck now
2006 2500HD, 4x4, QC LWB, 285 Coopers

Luvnacummins · 06-08-2008, 07:07 PM

Quote:

Originally Posted by antwan718

How fast were you going that it was off though???? Either way thats a huge gap.

80....

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I turn wrenches....

***05610on24s*** · 06-10-2008, 05:11 AM

my intown is horrible now since adding my 37s.... havent really calculated anything... I actually seem to be doing better the little i have drivin it on the highway.. 70 mile round trip everyday to work gets a little expensive so i dont drive the truck much.. Ill have to get it out and do some calculations...

__________________
05 w/ 07 Metal, SRT, Flares, DiPricol, II PS62 on ATS, AD150, MBRP, TST, 6.5" lift, 8 Bilsteins, 22's on 37's... Next up... Tranny
Redneck Engineering Low Curve, 6" out 0" up, Custom Paint, 100" RevTech, 6 Spd, 3" Primary, Billet Concepts Controls, MC Motorsports Reaper Wheels, DNA Sprockster

06-04-2008, 07:03 PM	#1 (permalink)
J-Mo Cummins Nut Join Date: Apr 2008 Location: baton rouge/new orleans louisiana Posts: 431 Thanks: 0 Thanked 0 Times in 0 Posts J-Mo's Truck Pics	35-37 mpg loss?? Im trying to decide between running 35s and 37s in a Toyo open country m/t. Im averaging about 20 mpg(hand calced) now. Im curious what the mpg loss would be with 35X12.50 or 37.13.50 if the difference between the two isn't that much id rather run the 37s thanks, J-Mo __________________ Black 08 6.7 QC auto 4x4 sport, AFE stage2, PDI 5" TBE 6" tip, Edge Jucie/att./hot, mp-8, egr delete, 4.5 fabtech, dual bilstiens, thuren trackbar, fox stabilizer, 35"toyo mt's, 20" black rockstars, tint, bed cover, srt hood.....more on the way

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06-04-2008, 07:55 PM	#2 (permalink)
Luvnacummins TECH SPECIALIST Join Date: Jan 2007 Location: Twin Falls Idaho Posts: 1,290 Thanks: 9 Thanked 0 Times in 0 Posts Luvnacummins's Truck Pics	cruising down the freeway mine went up because it dropped my rpms!!:thumbsup __________________ I turn wrenches....

06-04-2008, 07:58 PM	#3 (permalink)
KBCummins5.9 Cummins Fan Join Date: Jun 2008 Location: New Mexico Posts: 38 Thanks: 0 Thanked 0 Times in 0 Posts KBCummins5.9's Truck Pics	Im running 37's and geting anywhere from 14-16 in town/ hwy about 18-20 __________________ 2004 ram 3500 laramie, 4% tint, 6" superlift, 37/14in tires, Superlifts TruSpeed, 3500w amp twin 1800w subs, Banks six-gun & speed loader, Banks High-Ram intake, Banks Ram-air intake system, FASS fuel system, Aero exhaust, Exhaust break, Chrome Package.

06-04-2008, 08:06 PM	#4 (permalink)
1BadOilBurnerN-Lv Diesel Freak Join Date: Mar 2008 Location: Lost Wage's Nevada Posts: 862 Thanks: 22 Thanked 17 Times in 13 Posts 1BadOilBurnerN-Lv's Truck Pics	35's for in town 37's highway . I had 35's i got about 16-17 in town , highway was only about 17-18 , Once i got my 37's i checked it 18.5 in town 21-23 highway . That was after my programmer and speedo recalibration . All was hand calculated :thumbsup __________________ 2000 2500 sport extended cab short box , 5-speed. 6 inch miter cut stacks , silencer ring M.I.A. , B.H.A.F. 355 gears , 6 inch long arm rcd lift and 37's SuperChips , fass pump

06-04-2008, 08:15 PM	#5 (permalink)
TacSat1 Cummins Nut Join Date: Dec 2007 Location: Wamego/Manhattan, KS Posts: 422 Thanks: 7 Thanked 2 Times in 2 Posts TacSat1's Truck Pics	with 35"/37"s you speedo will read 65, in actuality you are moving at 70-72, which is in the sweet spot of 1600 - 1800 RPMS. __________________ 2003 Dodge 2500, S.O., 48RE, 4x4, QC/LB, ISSPRO EGT, Boost, Trans Temp Gauges, Airaid MXP intake and 4" MBRP exhaust, Smarty on #5, Amsoil in the engine and a Transgo Shift kit

06-04-2008, 08:29 PM	#6 (permalink)
smkstk Diesel Head Join Date: Jan 2008 Location: Rapid City Michigan Posts: 3,132 Thanks: 5 Thanked 17 Times in 17 Posts smkstk's Truck Pics	bigger tire bigger mass, more mass more power to get moving, so like stated above, smaller tires for more town driving, bigger tires for more highway driving. __________________ Global climate change is natural phenomenon, exploited by the unscrupulous, for political and monetary gain.

06-05-2008, 01:50 AM	#7 (permalink)
Luvnacummins TECH SPECIALIST Join Date: Jan 2007 Location: Twin Falls Idaho Posts: 1,290 Thanks: 9 Thanked 0 Times in 0 Posts Luvnacummins's Truck Pics	on my truck according to my gps the speedo was off 13 mph!!! __________________ I turn wrenches....

06-05-2008, 10:43 AM	#9 (permalink)
terminaltsi Diesel Head Join Date: Apr 2008 Location: Lou-evil KY Posts: 1,053 Thanks: 11 Thanked 9 Times in 9 Posts terminaltsi's Truck Pics	the faster you go, the more the speedo will be off. __________________ '99 2500 5 speed, 4x4, gauges,Quadzilla ADR, Smarty, BHAF, 5" turboback, 315/75/16 maxxis bighorns, Airdog, 13" Valair,3000k HID's, HID off road spotlights, LED back up lights, LED interior lights,alpine/cerwin-vega/mmats audio.

06-08-2008, 07:01 PM	#10 (permalink)
dieselrambud Cummins Enthusiast Join Date: Mar 2008 Location: West Tennessee Posts: 247 Thanks: 0 Thanked 0 Times in 0 Posts dieselrambud's Truck Pics	With 37s my speedo is off 14.5%. Best I have ever got w/stock tires is 16mpg highway. Yesterday got 14 mpg highway w/ 37s. All hand calculated. __________________ 2008 2500HD, 4x4, megacab, 6-auto, Rize 8" lift, 37"x12.5" Pro Comp Xtreme ATs, Dick Cepek 17x9, 35% front tint, Bilstein 5100s-Wife's truck now 2006 2500HD, 4x4, QC LWB, 285 Coopers

06-10-2008, 05:11 AM	#12 (permalink)
*05610on24s* Cummins Nut Join Date: Sep 2006 Location: Terre Haute, IN Posts: 336 Thanks: 0 Thanked 1 Time in 1 Post 05610on24s's Truck Pics	my intown is horrible now since adding my 37s.... havent really calculated anything... I actually seem to be doing better the little i have drivin it on the highway.. 70 mile round trip everyday to work gets a little expensive so i dont drive the truck much.. Ill have to get it out and do some calculations... __________________ 05 w/ 07 Metal, SRT, Flares, DiPricol, II PS62 on ATS, AD150, MBRP, TST, 6.5" lift, 8 Bilsteins, 22's on 37's... Next up... Tranny Redneck Engineering Low Curve, 6" out 0" up, Custom Paint, 100" RevTech, 6 Spd, 3" Primary, Billet Concepts Controls, MC Motorsports Reaper Wheels, DNA Sprockster