?? guys is this normal ??

[XcumminsX]

OK guys, i look like this ----> evertime i wonder if my mileage is just way horrible for my truck set up or not... . First off let me say this. I have 315's (truck calobrated for 265's ) 4. 10 gears and a 48re trans. My computer says i am getting 13. 8 MPG:--) :--) :--) :--) :--) :--) :--) :--) . Is this off because of my tires or what... . I drive on average normal - get on it sometimes. Truck has 6000 miles on it. I drive about 70% city 30% highway. what do you guys think is going on here?

 

[nickleinonen]

is it saying mpg or is it in the l/100km mode? my truck says about ±13. 7 all the time, but i am in the liters per 100km mode [metric system] if i switch to the mpg mode, it reads about 17'ish. and my truck is 3. 73's with 315's and 6 speed.

 

[XcumminsX]

nope im sure..... its on mpg mode. .





Its also a 4x4

 

[Bunn]

XcumminsX-

Sorry I can't answer your question for you... But I was wondering if you are just doing the math for the larger tires, or do you have something that compensates for the tires installed on your truck?

 

[XcumminsX]

i am not doing the math, i am using the overhead system.

 

[Vaughn MacKenzie]

XCumminsX with your setup and auto transmission, 4x4 and big tires, running 70% city you should expect 14. 5-16mpg approx. Calculate by hand, not by the overhead, although the overhead can give you an indication of your mileage. Also don't forget to correct for speedometer error which will make your MPG look worse if you don't correct it.



Vaughn

 

[PBeaudoin]

I believe it is 1. 2 to 1. 3 MPG better then it reads. Thats what I figured out with my truck when I had the 315's on her. It also got better when I started running synthetics and it was broken in. This truck really loosens up after 20K or so. I was enjoying it very much till I upgraded to the 04. Now I back too the breaking in again stage. Hate it too.

How long have you had the 315's on? I hope you have better luck with them then I did mine. I got flat spots after 15-18K on them. I do allot of HWY running. They are incredible in snow though. Good luck.

 

[rbattelle]

Never trust the overhead... I have never found it to be accurate. It's normally at least 1 mpg off, usually more like 1. 5-2. 0.

 

[XcumminsX]

Thanks for all the info guys. I like the look of these tires and actually just got back from driving in the snow. They are pretty good. Ran it in 4wd right away. Only problem is when i went on rt 83 (only place that had salt) i could hear those little salt peddles hitting my truck. I hope they wont chip the paint :{ . Truck looks cool with some snow on it, i cant wait for a blizzard there will be some serious snow-offroading. This week i also get my 2" leveling kit on.

 

[PBeaudoin]

Let me correct myself. I checked mine when I had the stock tires on it. I found mine to be pretty close. Never is one perfect. When I made my statement I was saying if all was correct with stock tires& comp. then the difference is 1. 2-1. 3 MPG better then on the comp with 315's. Each time you fill, if you do not 100% fill it to the top, then you will never get an accurate reading doing any math. My comp has been fairly close on my 02, 03 and 04. less then 1MPG per gal off. You can usually determine how far its off in a couple of true fill ups. I believe your reading X 9% to get the reading for the 315-70-17 upgraded tires. Don't forget the 315's turn less per mile then stock, so if you even use miles divide by gallons, its still not accurate. It took me along time to really figure this out... jarhead that I am. For those of you that don't get it either like me, you need to think it out too.

 

[XcumminsX]

hmm the last time i was trying to fill my tank all the way up... ... ... ... ..... 5 minutes later i gave up because i was still trying to top it off . What is with that. .

 

[Bfulgham]

14 MPG? Have you reset you overhead?

Bob

 

[XcumminsX]

plenty of times

 

[PBeaudoin]

If this helps... I am also getting pretty bad MPG in the city. I am getting 14. 3 to 14. 9 with stock tires, and 17. 5 to 19. 6 on the hwy. I have to stay at 65 to get the higher number. As I said it does get better with synthetics and being broken in. I ready for synthetics at 1800 miles.

 

[BIG BOB]

Here is a link to calculate your tire difference.



Tire Calculator

 

[Greg Boardman-RIP]

My last fill up was horrible. Trip computer says 19. 7, I used 29. 999 gallons of diesel and went 379. 4 miles. That worked up to about 12. 6 mpg..... Injectors are way cool but a heavy foot and 4. 10 gears make for bald tires and low mileage. I usually average about 15 mpg XCX. Check it with the math. Every truck I have had was off on the overhead. Even stock, my wifes truck only sees 16 mpg.