Since I got my '99 back in November I only had been getting 220-230 a tank with an occassional 240 but never higher. I do have 265/75s and I do get on the throttle so I figured I was stuck with 15mpg all the time and this last week I threw in a new air filter (Puralator) and new clear tinted signal lenses and I got 275 miles (17.9mpg) to the tank which made me quite happy since I didn't alter my driving style one bit. I figured it was a fluke but I got almost 270 from my last one and I'm at a half a tank now and I'm already at 140 miles which before a half a tank would be at 120 if I was lucky.

I had a new filter in it back in November so it must have been the clear signals that did it. I definetly recommend them.

 

haha, congrats! now if only my clear signal lenses added mpg...

 

clear signal = better gas mpg - ok

 

The new lenses are glass smooth compared to my old lenses which one was cracked so the aerodynamic drag was hurting my mpg I think.

 

hah, wow. i too put in a new air filter which increased my mpg by 2 or so, so far.

i get about 240 to the tank, thanks to mostly city driving.

 

I was happy when I hit 240;I drive at 70+ on the 10 mile stretch of highway when I go to work and the rest is generally around town so if I can stay at 17+mpg I'll be content. My mom's a mellow driver in her '99 Limited and she always sees aroud 260 so I figured 240 would be the high point for my truck.
With my '97 5speed I never got less than 270 a tank and I drove that the same way.

 

this seagull crapped on my truck the other week - and it must have been a very un-aerodynamic crap because my MPG dropped down to like 12 mpgs until I washed it off!

 

I took the valve stem caps off, reducing the rotational mass of each wheel. You guys should try it too.

 

LMAO!

 

If they were TRD valve stem caps you could get more HP tho' and they're more areodynamic.

 

thats freakin awesome

 

Geez! I am running Wal-Mart special metal-bling caps! Now I know why my economy has dropped by 20%-30%

I'll be right back!

-S

 

Probably just your fuel gauge lying to you. Pretty soon you'll have done 270 miles on less than 1/2 tank. Then, without warning, the engine will die while in heavy traffic, and you will be the catalyst for the wrecks.

 

you dont determine mpg by your fuel guage. you determine it based on your trip meter and the number of gallons at your next fill up.

 

I wonder if it's related to fuel formulation changeover? This is around the time some states switch from oxy-fuel (-10% mileage hit) to standard blend.

 

"Burns cleaner" but you burn more. Gee I wonder. It's probably worse for the environment using the blend.

 

Yeah,it is about time for the Methanol to be dropped from our gas and that might be the difference.

 

I wish my tank was larger... I too run around 240 miles per tank, running 265/75/16's BFG's.
My ford has a 29 gal tank... now thats nice! But the diesel prices SUCK!