It is currently Thu Mar 28, 2024 9:19 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 32 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Most efficient driving speed?
PostPosted: Tue Jan 10, 2006 1:37 pm 
Offline
LOST Newbie

Joined: Thu Dec 29, 2005 4:50 pm
Posts: 36
'Just curious whether any of you out there have 'experimented' a little with your driving speeds (mainly talking out-of-town/highway here) to see which speed gives you the best mileage? Most sources I've seen talk about ideal efficiency being reached at between 40 and 60mph, with efficiency dropping off pretty significantly over 60mph:

http://www.howstuffworks.com/question477.htm

Mine seems to be best (to the extent that mileage computer can be trusted) in the high 50s/low60s.

I've decided my best solution is to find a way to be constantly driving DOWNHILL :)

_________________
Coyotefred
Prairies of Western Nebraska
'02 Silver KJ Limited 4x4 3.7L
Stock for now


Top
 Profile  
 
 Post subject:
PostPosted: Wed Jan 11, 2006 11:16 am 
Offline
LOST Member
User avatar

Joined: Mon Nov 07, 2005 4:30 pm
Posts: 458
I drive 70 miles a day toa nd from work....67 of those miles are on the higway. Before I got my lift it seems to me that about 65 mph had the RPM's right at or just below 2000. That seemed to be my best milage. And after the lift it tends to be that same. Except now when my RPMs are at 2000 i'm actually going about 71-72 mph.

_________________
New 2008 Jeep Libby 4X4 on 22s!!!
12" Sub, Pioneer Head Unit, Pioneer Door Speakers, Lineage Motorsport Ground kit, Borla Exhaust, Carbon Fiber CAI
http://www.cardomain.com/ride/2943514/1

2004 Renny 4X4-Lifted on 32's!! IS NOW RETIRED
2.5" RRO OTT Lift & 32" BFG LT's
http://www.cardomain.com/ride/2205322


Top
 Profile  
 
 Post subject:
PostPosted: Thu Jan 12, 2006 10:54 am 
Offline
LOST Newbie

Joined: Thu Jul 28, 2005 10:20 pm
Posts: 78
Location: Tampa Florida
IMO, between 50 and 60 mph unless you're driving a CRD Libby, in which case I'd say between ~58 and 65 mph.

You want to go just slightly faster than the slowest speed that you can engage your highest gear and not "lug" the engine. My auto tranny locks up at about 45 mph, so I'd say that 50 mph is probably pretty close to ideal with the stock tires (but I can't stand to go THAT slow on long trips, so I do ~60). If you're running oversize tires (lower RPM's for the same speed), you might need to go a little faster (than 50) to achieve your best mileage.

Luis

_________________
2005 Silver Liberty Renegade Rocky Mountain Edition 4x4 with Tow Pkg, Trac-Loc. Have had CJ5, CJ7, and a '99 TJ.


Top
 Profile  
 
 Post subject:
PostPosted: Thu Jan 12, 2006 12:41 pm 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Sun Nov 06, 2005 5:30 am
Posts: 1036
Location: Stillwater, MN
65 mph nets me 17 mpg with 255/70's and a rusty's lift

_________________
'02 KJ Sport V6 4x4
3/8" Clevis lift
Rusty's 2.5 lift
255/70/R16 Fleet Farm All Terrain (yes they work)
Class 3 hitch
Hellas
Police Scanner/CB radio
LOST #: JH061986
Image


Top
 Profile  
 
 Post subject:
PostPosted: Thu Feb 02, 2006 12:24 pm 
Offline
This member has been Banned

Joined: Fri Jul 15, 2005 10:20 am
Posts: 1100
Location: TEXAS
66 MPH is my best time/fuel effeciency... 23+MPG

45MPH nets me about 27MPG...Yes I do drive this slow on day to day trips under 25 miles one way. Ain't hardly no time diff.


Top
 Profile  
 
 Post subject:
PostPosted: Sat Feb 18, 2006 5:41 am 
Offline
LOST Member
User avatar

Joined: Sun Jan 15, 2006 1:21 am
Posts: 170
Location: Cordova, TN for summer
just took a 170 mile trip home, 20 of which at the end of the trip were stop and go behind a school bus (i hate public transportation)....i just got the libby in january, but when i took the trip down to school i went anywhere from 78-85, lets say about 82 avg....i got 16.8mpg. I took the trip back the other day, went 70, got 22.1 mpg. 20 of those were horrible city driving conditions (constant acceleration and stop/go with almost no cruising). i'm betting i coulda got about 22.5 without those lousy 20 miles

_________________
2004 KJ Sport 4x4 - Maroon
235/70/16 Firestone Destination A/T
T-Case and Engine Skids
Husky Front Liners
Escort PASSPORT-X50 Radar hardwired HIGH
ALPINE 9857 w/ full iPod controls
Infinity BassLink I Sub


Top
 Profile  
 
 Post subject:
PostPosted: Mon Mar 20, 2006 5:42 pm 
Offline
Lifetime Member
Lifetime Member

Joined: Mon Jul 11, 2005 1:03 pm
Posts: 8052
Location: Kentuckeeee
Ive gotten 23-24mpg doing 40-45 before. Up around 60-65 I get 21-22mpg. If Im going under 40mph Ill turn o/d off and lock the torque and I get around 23mpg.

_________________
LOST KJ'S
Where are you going???
Current Jeep: 2004 Jeep Liberty
-Atlantic Blue
-Air Ride Rear Suspension ; OME/Rustys Lift ; Powertrax Locker ; Moog Lower Ball-Joints ; 245/70/16 Yokohama Geolander A/T-S's on MOABS ; Flowmaster 50 SUV
Lost #007082
http://www.cardomain.com/id/jeepjeepster


Top
 Profile  
 
 Post subject:
PostPosted: Mon Apr 10, 2006 4:59 am 
Offline
Banned For Abuse on LostJeeps.com
User avatar

Joined: Thu Jul 07, 2005 12:40 pm
Posts: 2353
Location: Kettering, Ohio
I drive fairly aggressively at get about 17.5 in mostly suburban driving. This seems to be a bit higher than average for non-freeway driving. The 6spd is the difference, i guess?

My only tank of at least 75% freeway netted me 21 mpg, but I was humping it pretty well (80-85).

_________________
LOST # 633
'05 KJ 3.7L/6spd/241 245/75/16 MT's
'88 MJ 4.0L/AW4/231 SWB HPD30 & trac-loc D44 w/3.73's
A dirty Jeep is a happy Jeep


Top
 Profile  
 
 Post subject:
PostPosted: Sat Jun 10, 2006 8:17 pm 
Offline
LOST Newbie

Joined: Mon Nov 28, 2005 1:06 am
Posts: 82
Location: Newark, OH
Believe it or not I've notice I get similar mileage at 83mph as I do at 58, 23 or 24mpg. I drive from AZ to OH a couple of times a year and when I do I ONLY stop for gas so that’s from top of tank till empty.

_________________
02' Renegade 4x4
3.7L V6
CB, XM radio

visit my cardomain page


Top
 Profile  
 
 Post subject:
PostPosted: Sat Jun 10, 2006 9:27 pm 
Offline
Master of the Blender
User avatar

Joined: Thu Jul 07, 2005 4:21 pm
Posts: 2804
Location: Margaritaville
I've driven from Phoenix to Albuquerque many times in my Sport, and with the cruise set at 75 on the freeway I can average 22mpg. Best yet was about 23.5, but I was driving in rain on that one and had slowed to about 50 along a lot of the route; I hate driving at speeds too fast for the road conditions.

_________________
Kevin
AD5VG
Just another red Jeep in the world...
L.O.S.T. #KB051963


Top
 Profile  
 
 Post subject:
PostPosted: Sat Dec 16, 2006 12:47 am 
Offline
LOST Junkie

Joined: Sun Nov 19, 2006 1:36 am
Posts: 507
mine locks the torque converter in O/D at 61mph, unlocks it at 59, if exceed 61 then set cruise for 60, the computer says a steady 27-28 mpg on level hiway. @1900rpm

_________________
Admin note:
This account has been deactivated.


Top
 Profile  
 
 Post subject:
PostPosted: Thu Mar 29, 2007 5:49 am 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Sat Jan 06, 2007 1:54 am
Posts: 5827
Location: 7,000 feet, Zuni Mountains, New Mexico
My driving conditions vary due to wind and hills, but I seem to always get at least 20 mpg running between 65 - 70 mph. I would say that 1800 - 2000 RPM’s provides the best mileage gains. I’ve actually recorded 20 mpg at speeds as high as 75 mph. The best mileage recorded is 22 mpg running 70 mph. My Jeep is all factory beside the shift kit, but I hope to squeeze a few more mpg somehow. My first upgrade will be a aeroturbine muffler. I’m pretty sure this will provide at least a one mile per gallon increase.

_________________
2015 Ram Ecodiesel/Big Horn/4x4/Quad Cab
2016 Arctic Fox 22G/Onboard 2500 LP Cummins Onan Generator/160 Watt Solar Panel

I took the road less traveled. Now I'm LOST.


Top
 Profile  
 
 Post subject:
PostPosted: Wed May 09, 2007 5:05 pm 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Sat Jul 16, 2005 10:46 am
Posts: 798
Location: Williamson, NY
With my 5-speed in 5th gear at 60-62mph (Speed limits on the expressways in NY are still 55mph), cruise control on and RPM's about 2150, I average about 18.5 mpg with my mods (see signature). Next I'll be experimenting with acetone. Mods to come may include the Fitch catalyst and Race Ace louvres.

_________________
2003 Renegade 4X4 5-Speed, Bright Silver *TRADED for 2013 Wrangler*
PIAA 520 Auxiliary Lights
Garmin GPSMAP 76S
DynoMax Ultra Flow SS Muffler
Amsoil Ea "Absolute Efficiency" Air Filter
Nokian Vatiiva 235/70/R16 Tires
Pixeldzn's "RENEGADE" decals
Support the 2nd Amendment - It's your right!


Top
 Profile  
 
 Post subject: 29.4 miles to the gallon
PostPosted: Sun Jun 17, 2007 4:29 am 
Offline
LOST Newbie
User avatar

Joined: Sun Jun 10, 2007 4:48 pm
Posts: 17
Location: Fairbanks, Alaska
The best mileage I have had thus far is 29.4.
Running several trips between Fairbanks and North Pole Alaska.
Flat 12 mile stretch that is currently in reconditioning. Speed Limit 45. My average speed was 40 with my tire pressure at 40psi. this has been a magic combonation for me. I wonder what will happen when I do a lift and tire combo... :lol:

_________________
Alaska... land of the true blue frozen through.
2004 Liberty Renegade... mostly stock.
Bridgestone Dueler A/T REVO
STOCK: Mopar Skids & Rock Rails
http://www.cardomain.com/ride/2666032
Fairbanks_KJ,
Member #133661


Top
 Profile  
 
 Post subject: Re: Most efficient driving speed?
PostPosted: Sat Mar 06, 2010 8:53 pm 
Offline
Lifetime Member
Lifetime Member
User avatar

Joined: Thu Apr 16, 2009 2:17 pm
Posts: 1334
Location: Cle Elum, Washington
I set the cruise at 57-58 around 1750+ RPM and at that I can get in the mid 30's on the highway.

_________________
2006 KJ CRD Ltd - Suncoast, GDE Eco, EGR Delete, After market T-Stat, Skid Row skids, V6 airbox, 2.5" Turbo back
2005 KJ CRD Sport-Suncoast, Transco, GDE Hot-GDE Trans, EGR Delete, Skid Row skids, V6 airbox, 2.5" Turbo back, After market S-Stat
1987 Suzuki LWB Samurai -diesel powered, custom 4 link coil suspension 38.5 SX Swampers


Top
 Profile  
 
 Post subject: Re: Most efficient driving speed?
PostPosted: Sat Mar 06, 2010 9:39 pm 
Offline
LOST Addict
User avatar

Joined: Thu Sep 13, 2007 1:28 am
Posts: 10686
Location: Some where in Colorado
Way to bring back an old thread :jester:

_________________
2008 KK Liberty Sport NIGHT OPS EDITION + GILLS
OEM & Custom Skids - Factory Tow Package - Rock Lizard Skink Super Sliders
Prototype JBA 4 Inch Lift - JBA UCA's - Flowmaster Super 44 OR - Whacked Resonator
Jet Stage 2 - RL Gecko Basket Rack - Custom Winch Bumper - Recon 10.5K Winch
Image


Top
 Profile  
 
 Post subject: Re: Most efficient driving speed?
PostPosted: Tue Mar 23, 2010 10:33 am 
Offline
Banned For Abuse on LostJeeps.com

Joined: Mon Feb 05, 2007 2:44 pm
Posts: 1856
Location: Buena Vista, CO
CRD Joe wrote:
I set the cruise at 57-58 around 1750+ RPM and at that I can get in the mid 30's on the highway.




How are you able to stay at 1750 rpm at 57-58 mph? At 60 mph, locked up in 5th gear, I am turning 1700 rpm. At 59 mph, the tranny downshifts into 4th, and the revs go higher, like over 2000 rpms.

_________________
2006 Sport CRD

Could the Aztecs have known, that in 2012 after a 4 year experiment, our country would cease to exist?


Top
 Profile  
 
 Post subject: Re: Most efficient driving speed?
PostPosted: Mon Mar 29, 2010 3:38 pm 
Offline
LOST Newbie
User avatar

Joined: Wed Dec 13, 2006 7:36 pm
Posts: 52
Location: ,VA
The last trip i took recently was from Va to Ga and i top my all time record of 36.5 and got 38.5 mpg with my CRD. What I do is Get her in 5th gear locked up and with cruise on i drop my speed back to 58 , 59 at 1625 rpm. she will hold that in cruise on the hills on the highway. I sometimes can go 57mph in 5th gear locked up if it is flat but i dont run on flat for long in Va.

_________________
05 liberty Limited CRD, 2" lift ,Goodyear 245 75 R16 on Moto Metal Wheels 16x9,SP Diesel Programer STAGE-II,K&N Air Fliter,Stainless steel door handles,vertical billet grill,Bermuda black LED tail lights,window vent cover,crome side mirror covers.ORM elephant hose,full skids,rock rails,


Top
 Profile  
 
 Post subject: Re: Most efficient driving speed?
PostPosted: Thu Apr 08, 2010 8:45 pm 
Offline
Moderator / Lifetime Member
Moderator / Lifetime Member

Joined: Thu Jul 07, 2005 5:49 pm
Posts: 27226
Location: NOW Southeastern Ohio/ Tanzania
74 MPH
at 1950 RPMs
and 21.5 MPG
hit the hills though and the 265-75s kill me :-)r
someday he'll finally throw the 4.10s in

_________________
MUDD'S MOTORSPORT'S We do IFS lift installs ,
03 OVERLAND EDITION /Kilby-Skidrow-Mopar-4XGuard skids/ 2.5 inch TOTAL CONTROL JBA coilovers -JBA Arms/MOABS-31 FALKEN WILDPEAK AT3W / 4.10's etc, 04 Kilimanjaro Edition loaded, plus 05 KJ limited


Top
 Profile  
 
 Post subject: Re: Most efficient driving speed?
PostPosted: Thu Apr 08, 2010 10:10 pm 
Offline
LOST Newbie

Joined: Thu Feb 25, 2010 12:47 pm
Posts: 43
1500rpm
52mph
24mpg

2007 lib 3.7


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 32 posts ]  Go to page 1, 2  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 5 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group. Color scheme by ColorizeIt!
Logo by pixeldecals.com