Bad MPG - What may be the issue?

Duh tires , I said wheels

 

I know, I added that change to my reply to be more clear, but even bigger wheels can weigh more and add to lower mpg and bigger wheels means bigger tires. The EPA says that for every 100 pounds taken out of the vehicle, the fuel economy is increased by 1-2 percent. The same applies if weight is added and there is a 1-2 percent loss.

 

They lie all the time, and you want us to have trust in what they say.........

 

Good luck dropping 100 lbs in wheel weight

 

Winter gas sucks. I average 20-21 mpg all warmer months with 30/70 city/ hiway with 71-73 mph cruising. The last few tanks I got maybe 18 mpg because it's freaking cold. I'm at 23k miles now so my test is as accurate as it gets

 

I believe the OEM size is 265/70R17 which is roughly 30"
255/75/17 is about 32".

Combine that with winter gas blend and a higher drag with the lift, your gas mileage is about right where it should be.

I'd hit 20's in the summer keeping it 65-70 hwy.

 

It is not about dropping 100 pounds in wheel weight. When you figure in the added weight of the tires and wheels you can very easily add 100 pounds to the truck. However even if not 100 pounds any 50 pounds lowers the mpg. In fact any added weight, even 1 pound, will lower mpg although not as evident in itself.
If you think about it some drivers might weigh 150 pounds and others 350 and that means lower MPG for the heavier people. Every pound counts no matter where it comes from.

 

Yeah sure , but you're trying to apply all that to something I didn't say , I said getting different wheels won't effect your mpg , and they won't unless you're worried about trying to factor the loss of a 1/4%


FWIW , I added over 100 lbs in tire weight , 200 lb commercial cap and 250 lbs of tools and I still get 16 MPG ( US gallons ) in winter

 

Best advice for gas mileage - don't get a tacoma. For the 4.0L, it really is between 15-21mpg. Some more, some less depending on how you drive and what you have(lift, tires, etc) and time of year.

 

If you do not trust the EPA at least trust the math.
http://ecomodder.com/forum/tool-aero-rolling-resistance.php

 

We have a pretty similar set up and I get about the same mpg.

 

Any change is a change and when added to other things it all adds up.

 

Number numbers.....
You can make them what you want...

I will tell you this/
Ran a trip to a few days in a row, just the truck, 7200 lbs, and then with the load 10400.
You know the fuel was the same on both trips. MPG were with in .2 I think running the numbers.
So from the EPA and your chart my MPG should be a lot better with out the extra weight. But it was not....

 

Most of those people are stock. Others have done heavy performance mods to counter the extra weight. For instance, I drove down to south padre with TheKidCatcher, who has a truck lifted 4'', 33'' km2s, 400 pounds of trail armor, bed rack, etc and he got 21 mpgs on the way down there. Same as me in a stock (at the time) truck. He was running a ton of after market performance mods from urd and the like. That being said, lifting and throwing on some heavy AT tires are a sure way to kill mileage.

 

So you loaded your tacoma to 10400 pounds and it did not change the MPG but .2 percent. Impossible!

 

If it just started happening once the cold hit this is your answer. I get 22 in the summer. 18-19 in the winter.

 

Have u checked your throttle body vavle? with time and mileage those tend to get really dirty and could cause bad mpg. It's good practice to clean or inspect annually.

 

You are not alone, my truck also suffers from poor gas mileage. There are several people on here that say "suck it up and deal with it...it's a truck". Well screw that, there has to be a way to get these trucks to improve their fuel mileage.

My wife's 4runner gets 21-22 mpg with 265/75r16 Nitto's and we have the same engine. And my 2003 supercharged 3.4L with 33's was at 17-18 mpg.

Honestly I suspect the engine management system. My theory is that the engine is seeing more fuel than it needs during certain driving conditions. I'm planning to install a wideband AFR meter and fuel calibrator to see if I can fine tune the fuel profile.


RJM

 

They pretty much do long highway trip at 65 mph , or live in a area that doesn't have many hills or stop and go driving.

Its a truck , Its not going to get great mileage. If you getting anything around 15-16 mpg with mixed city and highway your not doing to bad . Especially with a lift.