So the past month or so truck gas mileage has been dropping from my standard of 16 MPG (and by standard I mean I have had less then 5 tanks that were not 16 MPG)

Anyways... when my mileage dropped to 14 MPG I took it in for an oil change at the dealership and they also do an inspection (fluids, tire pressure, etc.). I leave the dealership.... still getting 14 MPG.

MPG eventually goes down to 12 MPG.

I decide to check my air filter, it's black, it must have got dirt on it then the moisture turned it muddy. I changed that and got back up to 14 MPG. Hrmm... now what... take it to a dealership "Yeah 14 MPG is normal... and it only has 5,000 miles on it so it's against policy for us to do a mileage diagonistic until it reaches 10,000 miles"

I eventually realize how important tire pressure is to gas mileage.... I check the tire pressure of my tires.... all 4 of them are at 20 PSI So I pumped them up to 30 PSI front 35 PSI back (as recommended on my door label) and my very next tank I just got 16.7 MPG

Moral of the story: Never trust someone elses (AKA the dealerships) work without double checking it.

P.S. Excluding my 16.7 MPG # all other MPG numbers were calculated multiple tanks.

 

Tire pressure make a haaauuuuuuge difference. If you don't mind a stiff ride you can over-inflate them a squeeze in a few extra miles per tank.

 

My vote if for getting your lift put on so you can ditch those crapyears


but glad ur getting better MPG

 

Funny you mention this.

I just bought a new 06 FX4 I thought the LF tire looked a little low so I check them all. The lowest was 21psi and the highest was 24psi.

My previous tank was 16ish and the following tank was 18.8

Oh and btw: My door label calls for 30/30psi (front and rear)

Rich

 

your door label varies depending on what brand of tire you have on from the factory....

 

what kinda tire pressure for 33"X12.5X15's?

 

depends on the tire and load range of the tire....if you look on the side of the tire, it will have it there......but most 33x12.5x15 that you will put on a Ranger which will be load ranger C will be a max of 35 PSI....

 

I am Running from Dallas/FtWorth to San Antone Friday...I guess I am going to try to put in a few extra pounds to get better MPG. How high should I go 33-35?

 

go with what the MAX on the tire says.....i would bet if you look it is 35psi......dont exced that though because your tire wear will go WAY down....

 

alot of it is based on the wheel width with that tire, you still want to keep as much contact patch as possible, and you can't run max psi on a 33x12.5x15 on a 15x8, only 25% of the tire would be on the ground, which is hwy they recommend a 15x10 for 12.5" wide tires.

i run what ever air gets me the best contact patch on flat concrete with the most psi.

 

x2

 

x3......i have 28psi in the rear and 35psi in the front......

 

Ya a lot of pressure in the tires can help to get better MPG, but I always hear that you may want to run a little less in the back because there is just no weight, and it will just hop like crazy.

 

hmm... i always get crap mileage.... and i dont think i've ever thought to check the tire pressure, even though that sounds so obvious.... i think i'll make a trip out to see what mine are at. i know i've never personally put air in my tires... so god only knows when the last time they were checked or anything....

ill post numbers later when i check them.

 

Over inflating the tires is something I always do on a road trip to help milage.

The down side it that you tend to wear out the center of the tread quicker. But keeping the tires rotated evens out the wear generally.

Up here in the north you gotta replace the tires before they get too bald anyway so it's not too big a deal for me. If you live in dry climates and run your tires til you can see the air swimming around.. you might wanna keep the pressures normal.

Rich

 

i have to check this out.... i'm getting 14 mpg too... after programmer...

 

when a new car/truck comes in with only 5k at the dealer, i watch people go through and not check anything. they dont recc. air filters for like 10k so they dont look, but i dont think u can put a time on it, its more of what type of driving you do.
i work at a dealer so i know what people do. you wont get a good inspection untill like 20k on ur truck, so i'd say check ur air filter urself. they rip you off anyways at the dealer. its like $10 more for a filter.

 

i checked my tires the other day... they said 44 psi max.

here's what all four tires actually had-

Front Left- 28 psi
Front Right- 29 psi

Rear Left- 29.5 psi
Rear Right- 29 psi


i went ahead and put both Front tires at 40 psi, and put both Rear tires at 38 psi... should i let some air out??? add more in??? keep it at what it is now??? i have no long road trips in the near future... and i rotate my tires every 3000 (at every oil change).

 

I've been running 35-psi in the fronts and 32-psi in the rears of my GoodYear Wrangers with no problems.

 

which Wranglers do you have?? the stock RT/s's or did you upgrade to something better?? lol... i had the crap stock ones for only a few weeks... they were cupping badly and the first real mod i had to do was tires... i hated those things with a passion.

 

i got goodyear wrangler at/s 20"wheels 34" tires.it says max pressure 80 and the load rating is load "E" but my 2 front ones have 51.5 and pass rear is 48 and driverside rear is 51 should i add more air in?? to what pressure? iam getting really crappy mileage and never thought it would be tires

 

40 psi is SOOO much

I would go max of 35

 

Stock Wranglers here. They are fine for what I need in a tire, however this will be the 1st winter with them, so I can't comment on how they'll handle in the snow and ice. These seem to get me thru everything I need to get thru. The work well on dry and wet road. Sure, they're break loose on a wet road if I want them, but under normal driving, they're fine for me.

 

In every car/trailer I have ever owned, have always gone 5 psi over what the tire says. Never, ever had any weird wear patterns.

Most of my driving is dry roads, occasionally rain, never mud.

 

i JUST fixed my mileage problem yesterday too. turned out, after a few meets, my air filter was CAKED. i'm getting ~20 mpg now.. maybe more!