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I've heard it takes a little while to break in the pathfinder, but my mileage is getting worse. I put larger tires on it, and I know that will hurt it a little, but I was averaging about 15.7 w/ 285/70/16 tires, and now I'm down to 14.1 mpg with the same tires. I have 5,000 miles on the vehicle, and the tires have been on for about 4600 of that. What's going on? Any suggestions or comments?

I also have a K&N air intake system, and a Flowmaster 3-chamber muffler. What kind of mileage are y'all getting with the stock tires? Maybe I'll go back to them, or at least something similar.

My Pathfinder is an 07 4x4 if that helps any. Thanks!!!

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I've heard it takes a little while to break in the pathfinder, but my mileage is getting worse. I put larger tires on it, and I know that will hurt it a little, but I was averaging about 15.7 w/ 285/70/16 tires, and now I'm down to 14.1 mpg with the same tires. I have 5,000 miles on the vehicle, and the tires have been on for about 4600 of that. What's going on? Any suggestions or comments?

I also have a K&N air intake system, and a Flowmaster 3-chamber muffler. What kind of mileage are y'all getting with the stock tires? Maybe I'll go back to them, or at least something similar.

My Pathfinder is an 07 4x4 if that helps any. Thanks!!!

 

 

I've got about 1500 miles on an 07 S model PF that started out at about 150 pounds lighter than the SE or LE models as it doesn't have a sunroof, stock tires are 245/75/16 General Grabber AW's turning at about 685 revs per mile, run at 44 psi as it says on the tire sidewall, not the 35 on the door post, the ride is fine. I leave the spare in the garage when doing local travel, and carry a small compressor and can of Flat-fix, which got rid of another 60 pounds (I haven't had to change out a flat on the road in likely 20 years or more)...when I removed the spare the truck sat up almost an inch measured from the top of the rear tire to the body. I got rid of the rails on top about the second day as I never use those. Even before taking the truck off the lot I had the dealership check and adjust front and rear alignment, which was slightly out. I usually fuel the truck to half a tank for local travel, rather than carry around an extra 50 pounds of unused gasoline in the tank.

 

I have family visiting for the summer so have kept the third seat in, but will shed that for another 50 pound saving later, and just install it when needed. Sometime I'd like to get rid of the stock front and 2nd row seats and put in 4 lightweight Recaro seats or similar for likely another 100 pound or more saving. I'll be getting some ultra-light alloy wheels and narrower lightweight low-rolling-resistance tires, something like a 235/85/16 or something similar in a 17" and turning at about 650 revs per mile, to get rid of about another 100 pounds for town and highway driving, and put offroad tires on steel for that use. Skining some areas of the underside of the truck such as rockers to frame, and rear diff to rear bumper may help, but I haven't looked at that yet. Little things like instaling Lexan covers over the fog light openings, installing some types of grill covers, getting smaller side mirrors all help smooth the front and sides.

 

There are a number of driving skills and fuel saving methods on sites such as Cleanmpg.com, priuschat.com, etc mainly for hybrids, but some of it applies to regular vehicles. One that I haven't tried yet is having the engine block heater plugged in for an hour or so to preheat the engine as fuel use is fairly high for the first 15 minutes or so until the engine gets fully warmed up.

 

So far I've been getting 18 - 19 mpg in town, 28 mpg at about 55 mph on secondary highways and about 25 mpg on 70 mph freeways. The service manager at the dealership tells me I should get about another 10% - 20% decrease in fuel consumption when the truck gets fully broken in at about 10,000 miles, so next year about this time and with a few mods I hope to be getting something close to 35 highway mpg and 25 in town.

 

Too bad Nissan didn't provide a 6 speed manual transmission option with these as is on the Frontiers, we could likely have gotten close to 40 mpg...service guy says a clutch and manual trans should slip right in and if I can find them for a reasonable price I may take a look at that.

 

If your gas mileage is getting worse from a current mod established baseline of 15.7 you may have a mechanical problem though. Hope that helps.

Edited by GreyBrick
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I've heard it takes a little while to break in the pathfinder, but my mileage is getting worse. I put larger tires on it, and I know that will hurt it a little, but I was averaging about 15.7 w/ 285/70/16 tires, and now I'm down to 14.1 mpg with the same tires. I have 5,000 miles on the vehicle, and the tires have been on for about 4600 of that. What's going on? Any suggestions or comments?

I also have a K&N air intake system, and a Flowmaster 3-chamber muffler. What kind of mileage are y'all getting with the stock tires? Maybe I'll go back to them, or at least something similar.

My Pathfinder is an 07 4x4 if that helps any. Thanks!!!

 

Assuming that your truck came with 245/75R16 tires, your speedometer (and odometer) are now reading 4.1% low - in other words, you are going 4.1% faster/longer than what the car thinks you are doing. You need to add that to your figures.

 

In addition, you have de-restricted the intake and exhaust, which means you flow more air. Which means that in order to keep the engine from running lean, the computer is adding more fuel. That means less mpg.

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I've heard it takes a little while to break in the pathfinder, but my mileage is getting worse. I put larger tires on it, and I know that will hurt it a little, but I was averaging about 15.7 w/ 285/70/16 tires, and now I'm down to 14.1 mpg with the same tires. I have 5,000 miles on the vehicle, and the tires have been on for about 4600 of that. What's going on? Any suggestions or comments?

I also have a K&N air intake system, and a Flowmaster 3-chamber muffler. What kind of mileage are y'all getting with the stock tires? Maybe I'll go back to them, or at least something similar.

My Pathfinder is an 07 4x4 if that helps any. Thanks!!!

 

 

Another thing that could be giving you poor gas mileage during the summer is AC usage. I haven't got around to doing this truck but on others I've stripped out the interior panels, seats and carpets and insulated everything from the roof down, including doors, using various products for different areas, like Dynamat self adhesive sheeting, closed cell foam rubber, spray in Polyurethane foam, heavy-duty hvac aluminum foil and tape, butyl rubber sheeting and spray on contact cement, etc. The products add about 30 pounds to the vehicle weight but once you get it cold inside your AC seldom kicks in and it should improve the PF because I find it's kind of loud inside anyway. Should be able to get this mod done for about $150 in parts and an afternoons work. Another benefit is that you open up the truck so you can spray in some anti-rust products at the same time.

 

AC usage can hurt your mpg by anywhere from 5% to 20% depending how you are running it, some folks only kick in the AC when they are coasting down hills and shut it off for flat sections or climbing and say that helps economy.

Edited by GreyBrick
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The original tires on the SE are 265/70/16.

As far as the de-restriction of airflow theory?!?!? I don't buy that.

I had larger tires, K&N, Flowmaster, and a Hypertech programmer on my 04 z71 tahoe. I also had a Yakima Mega Warrior on top, and I was getting about 22mpg on the highway...Way better than anyone was getting with their stock rides. I did each of those mods indidually and watched the mileage climb.

I asumed that the same would happen with the Pathy, but I'm seeing that my results are getting worse...doesn't make sense!!!

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As far as the de-restriction of airflow theory?!?!? I don't buy that.

 

Yep GhostPath has it about right for the PF I think. If you look on the K&N website here at the PF/Frontier power curve charts the air kits don't start giving any additional HP till about 3500 rpm, which is fine if you need HP for drag racing or hauling horse trailers up long hills or gum booting around, but I'm running between about 1100 and 1500 rpms in town and something just under 2000 rpm for freeway, and if I could drop those by 100 or 200 rpm I'd be a happy man. If you step on it and get above those rpms though that engine will take long huge drinks. Easy enough to check it out though, block off about 1/2 to 2/3 or more of your air filter with some plastic sheeting and duct tape, reset your mpg readout, tape a fresh egg end on to both your gas pedal and brake pedal and try driving like that for about 1/2 an hour, and see where you are at. Before you do that though go pump your tires up to the sidewall psi. Bet you'll be considerably above 20 mpg...take some extra eggs. I've heard driving barefoot and just using your toes also helps learn to run these trucks for economy, but there are some other tricks like using elevation gains such as building speed running downhill and coasting up the other side.

 

I know what you're feeling though, my other work truck is a 98 Yukon with 5.7 Vortec and I can average 25mpg easy with that just by staying off the gas. 2000 lb heavier truck, but interestingly enough it also came stock with P245/75/16 AT's in 35 psi BFG's. The PF has a really small torque band at the economy end because it's a lightweight engine imo and at those rpms you only have 50 or so HP to work with. Too bad we didn't get the 2.5 liter turbo-charged approved in North America...those are getting like 30 mpg's on diesel in the rest of the world, and with good low end torque as well.

Edited by GreyBrick
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Just finished a 250 mile Sunday family day in the mountains type of trip, with 6 adults, a large kid and about 50 pounds of ice and coolers, likely something just north of 1200 lbs of weight. AC was on at 2 most of the day, about a 20 mph headwind for about half the trip, with winds at about zero in the afternoon, so no tail winds to help back. About 50 miles of the 250 was driving slow through resort areas, some town driving, etc, and according to the trip counter averaged 24 mpg.

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I've heard it takes a little while to break in the pathfinder, but my mileage is getting worse. I put larger tires on it, and I know that will hurt it a little, but I was averaging about 15.7 w/ 285/70/16 tires, and now I'm down to 14.1 mpg with the same tires. I have 5,000 miles on the vehicle, and the tires have been on for about 4600 of that. What's going on? Any suggestions or comments?

I also have a K&N air intake system, and a Flowmaster 3-chamber muffler. What kind of mileage are y'all getting with the stock tires? Maybe I'll go back to them, or at least something similar.

My Pathfinder is an 07 4x4 if that helps any. Thanks!!!

 

 

There are a lot factors that you have to consider. Such as your driving style, how hard you were driving the vehicle. When you are comparing the MPG were you using the AC then, or are you using the AC a lot now? How does the Air filter look, does it need to be clean? When was the last time the oil was changed? Which motor oil grade did they use when they changed it? And to check the tire pressure of the pathy.

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Just finished a 250 mile Sunday family day in the mountains type of trip, with 6 adults, a large kid and about 50 pounds of ice and coolers, likely something just north of 1200 lbs of weight. AC was on at 2 most of the day, about a 20 mph headwind for about half the trip, with winds at about zero in the afternoon, so no tail winds to help back. About 50 miles of the 250 was driving slow through resort areas, some town driving, etc, and according to the trip counter averaged 24 mpg.

 

The truck only has 5,000 miles. The oil was changed two weeks ago, the air filter is very clean, and the tire pressure is up and filled with nitrogen. The gas mileage has increased quite a bit this weekend though...a little more highway driving.

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05 pathfinder se 4x4 52k on the odometer. with stock tires and wheels (the originals which i still have) the trip computer was showing between 20-22mpg by far the best. with 305/70r16 bfg mud terrains it dropped to around 13-14mpg. when i changed to the bfg all terrains of the same size i've been getting 16-17. you tread pattern can have alot to do with fuel economy. had the same senario with my 00 frontier muds got around 14mpg switched to Super Swamper STS all terrains and the milage jumped to around 18. bottom line bigger rubber equals more fricton equals bad fuel economy. the theory about mud tires is they create excess friction when the lugs fold under as your tire is rolling along. I switch to the oem wheels and tires in the winter months when i'm not driving in the sand as much to save $ on gas. just a few thoughts, hope they made sense.

ps i also have a k&n intake fipk gen II

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05 pathfinder se 4x4 52k on the odometer. with stock tires and wheels (the originals which i still have) the trip computer was showing between 20-22mpg by far the best. with 305/70r16 bfg mud terrains it dropped to around 13-14mpg. when i changed to the bfg all terrains of the same size i've been getting 16-17. you tread pattern can have alot to do with fuel economy. had the same senario with my 00 frontier muds got around 14mpg switched to Super Swamper STS all terrains and the milage jumped to around 18. bottom line bigger rubber equals more fricton equals bad fuel economy. the theory about mud tires is they create excess friction when the lugs fold under as your tire is rolling along. I switch to the oem wheels and tires in the winter months when i'm not driving in the sand as much to save $ on gas. just a few thoughts, hope they made sense.

ps i also have a k&n intake fipk gen II

 

 

What ever happened to those Mud Terrains?

 

 

 

What's up brudda? WAVEY

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What ever happened to those Mud Terrains?

What's up brudda? WAVEY

 

lol wuz up, hope your enjoying them, when did you get a pathfinder?

 

yes reseting the ecu (disconnect the battery for 15 min or so) will restore the factory default settings for the fuel map and save some fuel mileage for awhile

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lol wuz up, hope your enjoying them, when did you get a pathfinder?

 

I got it early this month..And yes, I am enjoying the MTs. I pulled a jeep out of a mudhole last month, thanks to those cleats.

Edited by X4X4R8D
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