Precise1 Posted September 11, 2005 Share Posted September 11, 2005 While wheel mass can influence, generally only on acceleration, not while maintaining speed. Then the inertia can actually help. Do you run cheap 'off brand' gas ? Have you tried different brands or even different grades. Have you used injector cleaner lately ? Check to see that all vacuum lines are attached under the hood and not cracked. B Link to comment Share on other sites More sharing options...
yowzaeric Posted September 12, 2005 Share Posted September 12, 2005 I"m getting combined 18mpg with my 2004 4x4. This is mainly back and forth in Detroit traffic (17 miles =45mins to an hour). I have 31's and the oversized SE roof rack and air dam thing. - I thought that I was getting bad mileage, but 13 -14 seems way off. Is your exhaust system pinched or dented? While it doesn't seem like much, the increased back pressure can do a number on performance. Link to comment Share on other sites More sharing options...
merlinx Posted September 12, 2005 Author Share Posted September 12, 2005 The exhaust is a cat back aftermarket. Sounds nice too. As for the hoses, Im pretty sure they are not cracked but if any vacuum hoses were cracked would that not make it run leaner? Same with the Fuel Injectors. There is no problem with the power and it idles fine. I have been using mostly Shell brand but I will try a different brand and see what happens. Also it is finally getting cooler here so I will be able to not run with the AC all the time. I will see if that makes a difference. This bites!!! Link to comment Share on other sites More sharing options...
XPLORx4 Posted September 12, 2005 Share Posted September 12, 2005 Merlinx- Lots of things affect fuel economy, especially driving style. If you're heavy on the gas and have to use the brake a lot to slow yourself down, those factors contribute to poor fuel economy. I recently bought a really cool device called a Scan Gauge which tells me lots of info about the car's sensors such as intake air temp, timing, TPS, coolant temp, etc. It also calculates gas mileage, both instantaneous and trip. It can help you determine what's going on, plus it reads and resets the computer check engine codes. Another way to tell if your truck is running at its optimum efficiency is to get an emissions test (whether you need one or not). The gas readings can help you understand how the truck is running and whether the exhaust has excess fuel in it or if your cats are clogged/melted. A test should be relatively inexpensive, and if it helps you find the problem and improve your gas mileage, it may pay for itself in a short time. Link to comment Share on other sites More sharing options...
DJ Dank Posted September 12, 2005 Share Posted September 12, 2005 (edited) I dunno, I get about 14-15 on the freeway on all my road trips with the car loaded down. When I FIRST the got the pathy and it was bone stock, I was getting like 16-18 with my tiny 235/70/15 pizza cutters. I've just accepted that I can't get any better than 14-15...its been that way for the past 2 years. Edited September 12, 2005 by DJ Dank Link to comment Share on other sites More sharing options...
XPLORx4 Posted September 12, 2005 Share Posted September 12, 2005 (edited) DJ- Your larger tires don't rotate as many times in a mile as the original tires. Unless you regeared for larger tires, your reported mileage is inaccurate (lower) because of the larger tire size. Edited September 12, 2005 by XPLORx4 Link to comment Share on other sites More sharing options...
DJ Dank Posted September 12, 2005 Share Posted September 12, 2005 DJ- Your larger tires don't rotate as many times in a mile as the original tires. Unless you regeared for larger tires, your reported mileage is inaccurate (lower) because of the larger tire size. You're right Dean...and I always forget that too... Actually my SE had 265/70/15's and thats equated to 29.6 inches...so how do you think I should compensate for the 31's in figuring out the gas mileage...? So your ScanGauge gives you an accurate mpg reading even with your larger tires? Link to comment Share on other sites More sharing options...
XPLORx4 Posted September 12, 2005 Share Posted September 12, 2005 The best way to determine your actual speed is by using a GPS receiver or by pacing a car with a known accurate speedometer. The Scan-Gauge has a setup preference that allows you to compensate for different tire sizes for the purpose of calculating fuel economy. Link to comment Share on other sites More sharing options...
FloydMax Posted September 12, 2005 Share Posted September 12, 2005 You're right Dean...and I always forget that too... Actually my SE had 265/70/15's and thats equated to 29.6 inches...so how do you think I should compensate for the 31's in figuring out the gas mileage...? So your ScanGauge gives you an accurate mpg reading even with your larger tires? Bigger tire diameter means fewer tire rotations per mile and throws the odometer out of whack. For example. my son's 1996 Pathy had 235X70X15 (eewww!) with a 27.85 dia. The BFG All-T KO's on it now are 31X10.5X15 (yes, they fit the 6.5" rim and yes, they fit the car and rub only on the absolute last 1/8 turn of the steering wheel...a place you don't like to go anyways 'cause it scrubs ya tires! The 31" BFG KO's are 11.3% bigger in diameter and circumference. They also weigh twice as much as the stock tire so its real easy to get in the habit of putting your foot in deep when starting out. The odometer calculation for "elapsed miles" has to be increased by 11.3% when calculating gas mileage. Big diff when you go from 14.5 city to 14.5 X 1.113 =16.14. That ain't bad for city driving. I swear I could get 18-19 MPG with his 96 Pathy on the highway. But I know you have to be patient, keep the foot "soft" and the revs below 2000. The '96 will do 60 mph at 2100 rpm. THAT saves gas if you just remain patient and unaggressive. As my Dad always said...."Gas is cheap, oil is cheap, tires are cheap, but the guy behind the wheel can drive real expensive." Skill...econo-driving takes skill. It saves a lot of money :type: and you get to keep your license. Link to comment Share on other sites More sharing options...
DJ Dank Posted September 12, 2005 Share Posted September 12, 2005 Yeah...with my tires there's only a 4.7% discrepency in the reading which IMO isn't that great...1-2mpg I've always figured... Link to comment Share on other sites More sharing options...
pathfinderlude Posted October 25, 2005 Share Posted October 25, 2005 Speaking of improving mpg, what is the tire psi on your rigs? I know the sticker on the door says 26psi cold, which I think is a bit low? I'm currently at 28 and am thinking of bumping it up to ~32. Is that too much? TIA Link to comment Share on other sites More sharing options...
vengeful Posted October 25, 2005 Share Posted October 25, 2005 I've been running 40 lately. I usually keep it about 35 though. Although, I'm not running stock size tires either. Link to comment Share on other sites More sharing options...
Trainman Posted October 25, 2005 Share Posted October 25, 2005 (edited) Speaking of improving mpg, what is the tire psi on your rigs? I know the sticker on the door says 26psi cold, which I think is a bit low? I'm currently at 28 and am thinking of bumping it up to ~32. Is that too much? TIA Depends on what tires you are running. On my LT rated tires, they can go to 80 psi. The tire shop recommends 45, so that is what they are at (same front/rear). Firm ride, good handling, good off road, even wear so far. But a P rated tire may only have a maximum of 40-50 psi (our van is 51 psi max), so you probably do not want to run 45 psi on those :eek: . Check your tires or ask your friendly tire shop that you bought the tires from or who sells your tires. Make sure you tell them how you are using the truck as that will impact what pressure to put in as well. Edited October 25, 2005 by Trainman Link to comment Share on other sites More sharing options...
dernt Posted October 27, 2005 Share Posted October 27, 2005 (edited) I just took a trip to Chicago this summer with my stock (cept for OME lift) 1997 2wd XE and I always use AC. I got 20 mpg and some of the driving was city, but very little. This was averaged over 13 gas stops and 3000 miles. When I got home, I added 18" Titan rims and BFG 265-60-18s which are about 30.5" diameter. I just calculated my mileage over 5 weeks of city driving and I got 16.9 mpg. My pathfinder has 138,000 miles. Edited October 27, 2005 by dernt Link to comment Share on other sites More sharing options...
yowzaeric Posted October 28, 2005 Share Posted October 28, 2005 I was looking through a few of the hybrid websites and many of the posts suggest running 1-2psi over to reduce the rolling resistance without adverse wear or handling. I've been running a set of Michelins like this for over 5000 miles and it seems to be working. I improved mpg by 2 on the highway. (I run from Michigan to CT twice a month) Course with gas prices moving downward again....... Link to comment Share on other sites More sharing options...
merlinx Posted October 28, 2005 Author Share Posted October 28, 2005 With the wheels Im running (18" 255/55 18) I run 35lbs. Funny with the Original wheels (15/235/75) on my LE the speedo was off and with the current wheels according to my GPS the MPH are right on. I think the overall dia is 29" still getting 14.5 average MPG street or highway Link to comment Share on other sites More sharing options...
IndianRider Posted November 18, 2005 Share Posted November 18, 2005 I swear I could get 18-19 MPG with his 96 Pathy on the highway. But I know you have to be patient, keep the foot "soft" and the revs below 2000. The '96 will do 60 mph at 2100 rpm. THAT saves gas if you just remain patient and unaggressive. 2100 rpm @ 60 mph ??? interesting .. .my 96 se, 4x4 is at 2300 rpm at 60 mph fully warm with torque convertor locked up .. bone stock .. motor, tires etc .. and i get 17.5mpg on the freeway mostly in cruise control and 15.5 mpg in city when driven gently .. Link to comment Share on other sites More sharing options...
kmgar99 Posted November 19, 2005 Share Posted November 19, 2005 My RPM's are 2500 RPM @ 70 MPH.....32" BFG AT KO's with a 2" AC lift...40 miles each way to and from work with six 10% incline grades that change elevation by 1,000 feet each. Up down Up Down Up Down Etc..... Link to comment Share on other sites More sharing options...
nick1716 Posted November 23, 2005 Share Posted November 23, 2005 so either my gas guage is totally messed up or im only get aboot 10 mpg.. it reads 1/8th of a tank and only 200 miles.. how many miles to the tank can any of you get?! Link to comment Share on other sites More sharing options...
94extreme Posted November 23, 2005 Share Posted November 23, 2005 My RPM's are 2500 RPM @ 70 MPH.....32" BFG AT KO's with a 2" AC lift...40 miles each way to and from work with six 10% incline grades that change elevation by 1,000 feet each. Up down Up Down Up Down Etc..... wow. i wish. i crank 3k at around 70. 31 MTs.. used to get about 14-15 but i drive less aggressivly and that seems to help a lot on the MPG department. not sure what it is yet but a little more. i also started running with 40 pounds of air in the tires. i get somewhere around 200-220mi/tank. 250 was my best todate. Link to comment Share on other sites More sharing options...
kmgar99 Posted November 23, 2005 Share Posted November 23, 2005 so either my gas guage is totally messed up or im only get aboot 10 mpg.. it reads 1/8th of a tank and only 200 miles.. how many miles to the tank can any of you get?! I usually get 210 - 220 per 17 gallons at fillup, which is like 12 - 13 MPG....I can get 230-240 per gallon if i stay behind the semi's on the up hills Link to comment Share on other sites More sharing options...
rokris8079 Posted November 23, 2005 Share Posted November 23, 2005 I have gotten over 300 miles on a tank with my 97. Plus it's in dier need of a tuneup. Granted these were on trips to maine so mostly highway but there was also plenty of stop and go traffic on the mass pike. I would say on average I get about 260 on a full tank with city and highway driving. As long as there isn't any long steep hills. Link to comment Share on other sites More sharing options...
herm Posted November 23, 2005 Share Posted November 23, 2005 Nick, You can't trust the guage in terms of 1/8 of a tank left at 200 miles, etc. - the only way to calculate mileage is by miles driven and gallons used. Then you need to adjust based on your increased tire size - which affects both speedo and odo readings. I factor in 10% to my 31 BFGs, so if I ran 200 miles on 20 gallons, that is 10 mpg, adjusted to 12 mpg, because I actually ran 220 miles (just chose that for the easy math). You have 33s, so you're actually covering more distance than the odometer states, and thus your mpg is a bit better than you may think. Toys on the roof will cost you 1-2 mpg, in my experience (boats, bikes, spare tires, jerry cans, even an empty, but large, roof basket). I take my roof rack off when I'm not in expedition mode. Speed (rpms) is the big factor. I get 18-19 mpg if I drive at 60mph in 5th gear. I get over 20 mpg in a cross-country off-road situation, in 4wd, at 45 mph. But I'll get as low as 10 -12 mpg if I'm running 80+ mph on the interstate, or in hill country, always pushing 4000+ rpm. Pressure on right foot is directly linked to drop in mpg. The sticker says 14-19, and that's pretty accurate. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now