MPG Drop...hmmm

[danny4runner]

SO, When I got my 07 SR5 V6 with stock 265/70/17 Bridgestone Duelers I was getting anywhere from 390-420 miles to the tank. Since August I've been running Goodyear Duratrac 265/70/17 and now I'm getting between 320-340 mostly 320 or so miles to the tank. My question is, is that a normal drop in MPGs for a little more tread or could something else be going on? almost 100 miles to the tank is a lot!!! no check engine lights, I'm at 43,000 miles.
Also what services should I be looking at doing around 50K? All I've done is Oil.....

THANKS!!!!

 

[12guns]

Heavier tire, prolly 6 ply w/ more aggressive tread. 1 mpg is normal. Sometimes more from what I've read.

 

[danny4runner]

Yeah I would be ok with 1MPG.... but I'm down almost 100 miles a tank! Killing me at the Pump! any suggestions? Air filter is clean.... If not I'll just stop watching it lol
:redbrick:

Heavier tire, prolly 6 ply w/ more aggressive tread. 1 mpg is normal. Sometimes more from what I've read.

 

[CJ3Flyr]

SO, When I got my 07 SR5 V6 with stock 265/70/17 Bridgestone Duelers I was getting anywhere from 390-420 miles to the tank. Since August I've been running Goodyear Duratrac 265/70/17 and now I'm getting between 320-340 mostly 320 or so miles to the tank. My question is, is that a normal drop in MPGs for a little more tread or could something else be going on? almost 100 miles to the tank is a lot!!! no check engine lights, I'm at 43,000 miles.
Also what services should I be looking at doing around 50K? All I've done is Oil.....

THANKS!!!!

The mpg sounds 'normal' to me. As far as maint is concerned you can go here: Toyota Parts and Service I'd look back as well as forward to make sure you're on the right track. Based on the Toyota recommendations I would recommend scrolling down and treat almost any T4R as if it towed.

 

[danny4runner]

thanks... hope gas doesn't hit $5 this summer lol

The mpg sounds 'normal' to me. As far as maint is concerned you can go here: Toyota Parts and Service I'd look back as well as forward to make sure you're on the right track. Based on the Toyota recommendations I would recommend scrolling down and treat almost any T4R as if it towed.

 

[RickC]

See if you can find the rolling resistance ratings for the two tires mentioned. That will directly affect mpg.

 

[pipspeak]

Sounds too much of a drop to be only the tire. I'm on about 55K and just did a bit of fual/air maintenance... cleaned throttle body, cleaned MAF and ran a can of BG44K through the gas tank. It seems to have boosted the mileage a little bit, especially on freeways. However, I did not notice a huge drop in mpg in the last year and generally get about 22-23 mpg (calculated manually) on the freeway.

 

[consigliero]

SO, When I got my 07 SR5 V6 with stock 265/70/17 Bridgestone Duelers I was getting anywhere from 390-420 miles to the tank. Since August I've been running Goodyear Duratrac 265/70/17 and now I'm getting between 320-340 mostly 320 or so miles to the tank. My question is, is that a normal drop in MPGs for a little more tread or could something else be going on? almost 100 miles to the tank is a lot!!! no check engine lights, I'm at 43,000 miles.
Also what services should I be looking at doing around 50K? All I've done is Oil.....

THANKS!!!!

Are you sure that you had before 265/70/17 stock tires? My 04 is on 265/65/17 this is stock tires , maybe in 06 stock was 265/70/17 but if not than can be different in mpg when you installed bigger tires, I think. Never the less 390-420 it's for me impossible on my tires , I have 350-380 but we have few highways in Poland .
Regards Marek

 

[Barefoot]

Got enough pressure in the new tires?

 

[IOP25]

That's about 14 mpg. Something else is up besides going up a half tire size. Is it a 6 or V8. I still get 18-20 in mine.

 

[toto]

MPG always drops in the winter due to the cold air and a different mix of gas additives ("winter gas"). Now that it's warming up, you might start seeing some improvement soon.

 

[SurferRob]

I have a 2005 V6 SR5 and have noticed a reduced mpg. Currently I have 99,000 miles and have had all the required/suggested services except the 90,000, money was tight. I noticed that just past 90,000 is when the reduction took place. I checked the air filter and the tire pressure. I believe it might be the age/miles on the spark plugs not being efficient. I think this only because of when the changes started. This weekend I am getting the 90,000 tune up, maybe I will see a difference.

 

[DaBoostCreep]

SO, When I got my 07 SR5 V6 with stock 265/70/17 Bridgestone Duelers I was getting anywhere from 390-420 miles to the tank. Since August I've been running Goodyear Duratrac 265/70/17 and now I'm getting between 320-340 mostly 320 or so miles to the tank.

Ok, your vehicle had one of two tire sizes in stock trim

265/70R16 or 265/65/R17

If you are now running a 265/70R17, you have added a larger tire, a heavier tire, and more rolling resistance. Your speedometer, and odometer are of course now off. They would be reading below the actual speed being traveled, which combined with the tire size increase itself is enough to make your calculations show nearly a 100 mile per tank loss.

You'd need to figure out how much larger the new tires are from manufacturer measurement, then multiply that increase, for instance 1.04 multiplied by the amount of miles the odometer reads per trip reset. This will help you arrive at a much more accurate MPG estimate.

For example I increased one size. Its a 4% difference in diameter. So I take my miles per tank, multiplied by 1.04 and I arrive at my correct(ish) actual miles traveled.

If 300 miles per tank were traveled according to the odometer, with adjustment, the actual mileage was really 312. Couple that with larger tires, and you're getting closer.

 

[nmsail]

Like someone said 14mpg is a big hit.

No funny noises or rough idle??

 

[howieb]

Exactly what I was thinking. I have an 07 which I bought used with about 33K miles, and I am getting 20.5 mpg in mixed driving 70% highway.

Ok, your vehicle had one of two tire sizes in stock trim

265/70R16 or 265/65/R17

If you are now running a 265/70R17, you have added a larger tire, a heavier tire, and more rolling resistance. Your speedometer, and odometer are of course now off. They would be reading below the actual speed being traveled, which combined with the tire size increase itself is enough to make your calculations show nearly a 100 mile per tank loss.

You'd need to figure out how much larger the new tires are from manufacturer measurement, then multiply that increase, for instance 1.04 multiplied by the amount of miles the odometer reads per trip reset. This will help you arrive at a much more accurate MPG estimate.

For example I increased one size. Its a 4% difference in diameter. So I take my miles per tank, multiplied by 1.04 and I arrive at my correct(ish) actual miles traveled.

If 300 miles per tank were traveled according to the odometer, with adjustment, the actual mileage was really 312. Couple that with larger tires, and you're getting closer.