is anyones mpg dropping

[jaslo]

dropped. I have been driving the same. Just wondering if they are putting more water in the gas. Its kind of odd that my mpg has dropped my 1 mpg.

[RyanbabZ71]

yep

 

Mainly cause i have more short trips and also let the truck idle in the morning to warm up

 

Also you have to factor in they may be using oxigenated gas which will lower your mpg.  They use this in the winter to cut down on pollution

[DigUout]

My MPG drops too in the winter for these reasons -

 

1.  Truck warms up for 20 mins every morning

2.  I use the defrost constantly (gets the heat going faster)

3.  I have to use 4WD fairly often

4.  The less O2 in cold air theory

 

I think you'll find you're not alone in this if you did a survey of guys in this site and their winter MPG -

[siume99]

1.  Truck warms up for 20 mins every morning

2.  I use the defrost constantly (gets the heat going faster)

3.  I have to use 4WD fairly often

4.  The less O2 in cold air theory

 

Actually, when the air gets colder, it contracts (gets more dense).  So you should get more O2 bang for your buck.

[Kansas Kid]

Don't forget that the ECM on these trucks will also adjust to the cold weather and give the motor more fuel in an attempt to help it warm up.  That will also decrease your fuel economy.

[Guest Friz]

Here's the rub;

Cold air is more dense than warm air. So a lower outside air temperature will cause a motor to run leaner. The onboard computers keep the fuel/air mix at an optimum ratio preset from the manufacturer. So to compensate for dense air, the computer gives the motor more fuel.

In older carbureted motors, cold air is a bonus, it would give a little more power for the same fuel.

[2000 GMC]

My gas milage started getting crappy back towards the end of September here in Anchorage.  Last two weeks it was really bad with the temp getting below zero and me letting the truck warm up in the morning.

[chevy4x4trucks]

IMO it's because you normally let the truck idle in the morning and I think that when the defroster is running it is using the A/C stuff so that would give you the same mpg's as running the A/C on full blast.

[95 Silverado]

remember to, all the lubricants in the drive train get thicker when cold, create more resistance, absorbs more power, it all adds up to lower mpg. ???

[siume99]

Here's the rub;

Cold air is more dense than warm air. So a lower outside air temperature will cause a motor to run leaner. The onboard computers keep the fuel/air mix at an optimum ratio preset from the manufacturer. So to compensate for dense air, the computer gives the motor more fuel.

I keep forgetting about that silly Mass A/F Sensor  :stupid: The cold lubricants and trying to compensate for them with a warm up routine in the morning don't help either.  I put 5w30 oil in my truck a few weeks back.  Has anyone else change their type of oil for the colder weather?  A friend at work uses 5w30 year round.  Is there any advantage to using 10w30 during the summer?

[GSXER2]

Here in SE MA I have noticed a mpg drop.As much as 1.5 mpg.Its been relatively warm most days so I would say its that OXY fuel we get around mid November.

[bassdog]

Here in SE MA I have noticed a mpg drop

 

 

Where in SE MA? I live in Worcester.

 

 

bassdog

[ryr8828]

Filled up today. Went from 16.5 to 14 mpg.

[chevy4x4trucks]

Filled up today. Went from 16.5 to 14 mpg.

16.5, I'm envious, I only get about 13, maybe 14 if I'm easy on the gas.  Although we do have reformulated gas here.  I think that may be the reason for my crummy mielage.

[Thumper]

If you guys think you have it bad - try filling up my 2500 Avalanche MAX - The Thirsty Vortec Rat.  Last tank was 9.3 around town and that is being nice to him.  Since then it has snowed and I have used the 4WD a couple of times (just to see how well it worked).  Also extended warmups will take their toll on mileage.

 

Soap box mode ((ON))

The part that really ticks me off is this BS "Oxygenated" gasoline.  They mix 10% Alcohol (ethyl or Methyl) with the gas and think they are doing the environment a big favor..  Get a clue Feds!  It takes twice as much alcohol to make the same amount of heat as an identicle quantity of gasoline.  Dillute the gasoline by 10% and yes - you will have less pollution per gallon of fuel, but it will take more fuel overall to do the same amount of work!  In the long run the consumer suffers, the atmosphere is still loaded up with pollutants..

Soap box mode ((OFF))

 

Merry Christmas fellow Truckers!