Poor Milage ?

With winter gas you do lose some mpg. I monitor mine on fuelly and lost about 25 on my tank, i would get 340 or so.

 

I was getting poor mileage in my 2013 DCLB so I sold it an bought a more economical 2003 Sequoia 4x4 (5300 lbs) v8 4spd auto and now I get a respectable 21+ mpg mixed driving. I shit you not.

 

I normally get about 18-19mpg, but my last tank of gas for about 16.6mpg. Winter gas sucks.

 

Same here. I hate winter blend gas!

 

to much stop and go!! That's what kills mpg.

 

Best I ever got in the summer with my 11 DC 4.0 6sp manual is a between 16 and 16.5 mpg. 265/75-C Duratracs, sliders, and various things in the bed. To be honest I have a lead foot so that isn't surprising. One fall mixed freeway (78 mph), highway (68 mph), and dirt road (20 mph to 50 moh) trip this year I calculated a bit over 15 mpg. The last identical trip on winter blend the mpg dropped 2 mpg to a hair over 13.

 

It's not just winter gas. Part of it is (winter fuel contains more butane), but that is only part of it.

PSI drops in colder temps, so you get more rolling resistance. Fluids in the transmission and differentials are colder and thicker, hurting efficiency. The engine also runs rich when it is cold.

 

Your point is well-taken, but I put the majority of the blame for this issue on the gas. I run high quality synthetic oil/lube (less affected by temp changes) in the engine, transmission, differentials, and transfer case. I check/correct my tire pressure pretty regularly. My truck spends nights in an attached garage, where the temp never drops below freezing and usually stays above 45'. Despite all of this, my mileage took its annual plunge over a month ago, when the gas blend shifted, despite unseasonably warm temps until about a week ago.