seriously bad MPG

[gear_grinder]

hi, my v8 sploder is getting about 11mpg average no matter how i drive it.

its probly been switched to winter gas around here (michigan), but still it sucks.

in the last 10k miles:
plugs
wires
fuel filter
air filter
exhaust system
3 oil changes
front diff fluid change
alignment (pulls to the left)


It doesnt run or idle funky, miss, or stink. i keep it @ or below 2k rpm accelication and usualy 55-60 is the fastest i cruize. i do mostly country driving.

i'm wondering what else it could be? there are no lights on in the dash but i had autozone scan it and the only thing is that a gastank pressure switch said it had a high reading. any ideas, i'm sick of having to put gas in this thing every day

 

[jremington59]

Are you running oversized tires?

 

[2000StreetRod]

Synthetics in axles?

Do you have synthetic lubricants in your front and rear axles? If not, the normal lubricant adds a lot of drag when the weather gets cold.

The faster your engine coolant temperature warms up the better mileage you'll get. The PCM richens the mixture based on ECT. If you have a viscous fluid cooling fan (stock) then it adds more load and cools more during cold weather.

Check your tire pressures. Cold temperatures lower the tire pressure increasing rolling friction.

This thread should be in the new fuel economy forum.

 

[gear_grinder]

i didnt know there was a fuel econ section, my bad.

31x10.5 per sig, BUT i do have 3.73 gears!

hmmmm, i'm getting some syn gear oil today.

ive thought about a taurus fan, how much would an e-fan help?

 

[Millertime1987]

The temps shouldn't be effecting the fluids that bad. Its hardly gotten into the 20's, have you always had that bad of mpg? Also when was the last time you cleaned the MAF?

 

[2000StreetRod]

radiator block

You could partially cover the grille like the truckers do. That would help your engine warm up faster.

I live in South Carolina where it doesn't get real cold so I don't know how much mileage improvement you'd get with an electric fan. Maybe some Northerners could respond.

 

[gear_grinder]

its been that bad sence last fall. and i cleaned the maf this past summer... i didnt help after i did.

 

[xMike87x]

Are you going by the odometer or the message center?

With 31s on your odometer will be slightly off thus making it seem like your getting terrible mpgs. I dont think the tire change will mess with the message center although im not positive on that either.

Mike

 

[gear_grinder]

my spedo aprox 7 m/h slow because of the tcase swap sooo idk, but it doesnt matter right now becasue its got hydro-knock lol