Sudden drop in MPGs?

I used to get around 15-16 city mpg on my commute to work and back. One day driving home from work I noticed that it was under 7mpg, but ended up going back up to 12 mpg by the time I got home. Now, my mpg is consistently hovering around 12-12.5 mpg for my local commute.

The only thing I've done is add my weld-on sliders. I doubt they could drop my mpgs that much from the added weight. Plus, I had them on for about 3 days before the sudden drop in mpgs. I put a large piece of cardboard in my garage under the truck to see if any fuel was leaking as well, but nothing so far. Could the mpg calculator be off?

Any ideas?

 

Winter gas blend

 

Temperature correlated fuel consumption, best MPG is when your auto is fully up to temperature.
Cold days + short commute + cold weather (anti-freeze blend) Gasoline = Worse fuel mileage.

 

Temp change( longer warm ups), air density, gas blend,
Could be a number of factors.

 

Mine dropped too. I was getting 20-22,now getting 16-18. Winter blend plus cold weather.

 

I've never had any of my other vehicles have a drop of mpg like this. My old mercedes c55 still averaged 16mpg with a 5.4 v8 in the winter with the same commute and my wife's acura with a 3.5 v6 still gets around 20mpg city; no change in mpgs with the same fuel (from the same gas station).

Also, the mileage dropped midway through the gas tank as you can see, not at the start of a new tank of gas.

 

Our Outback dropped from 27MPG to 18MPG... Outside temperature dropped 30 Degrees F. and we got 10" of snow.

 

https://www.tacomaworld.com/threads/poor-mpg-read-this.464679/ !!!

 

I saw that, so I put a big piece of cardboard under the truck in my garage to see if anything was dripping, nothing so far....

 

No snow here, all of our other vehicles maintain the same mpg. Just my truck.

 

Rough.

All I know is that the newer more "fuel efficient vehicles" need to align a wide set of parameters so that it can achieve optimum performance with regards to fuel economy and emissions. Air, Oil, and transmission temperature play a huge part in this, viscosity of fluids are important to how easy it is to move your vehicle.

 

I mean this in a serious way.. welcome to Tacoma ownership. Fuel economy defies all previous experience with other vehicles.

You may have an issue here, not speaking to that - but the Tacoma is a temperamental woman when it comes to minor factors that effect efficiency.

 

this sounds like full air filter..
seen it many times

 

My wifes 2016 Rav4 dropped about 3 mpgs. She's only getting 29.

 

I drove about 300 miles last Thurs with a cold front moving in (net drop of about 40 degrees avg over night), the winds were crazy ... dropped me about 5mpg total. Same thing happened on a long drive to a funeral out west a few weeks ago. Pay attention to conditions and expect mpg to adjust accordingly.

 

I noticed you're in Washington. Along with the recent cold weather I went from averaging about 18 mpgs on my round trip commute to about 15.

Not as much as you but it's the first vehicle I've ever owned that got noticably worse mpgs due to colder weather, let also 20%. Heater is weak too.

 

What he said

 

Understandable, I drive the truck like a granny because it's a truck, not a racecar and I still get terrible mpgs. I mean I love the truck, but this drop is atrocious.

 

sexist

 

...and redundant.