[zigbigadoru]

so my dad took my mustang up north for the winter for storage and noticed it got terrible gas mileage on the highway. he said he was doing 65-70 the whole way, not punishing it, and im assuming in 5th gear. When he got there and filled up he said it got only 20 mpg. any reason its getting this bad or is it nothing?

[stanglifemike]

20 MPG is pretty good in my opinion....

[casper gt]

nothing wrong with 20mpg on a gt

[1FUN4RD]

Driver mod??

[G.T. Rags]

ur car most likely has after market gears or the higher 3.27 gear ratio option

i get 20 on the highway with my 4.10's babying the shit out of her

[Jucostud]

20 is what i got out of my 96. That isn't bad

[zigbigadoru]

nope its stock 3.27 gears. how is 20 good considering i get 17 in the city? im pretty sure our cars are rated at like 27 highway arent they?

[Jucostud]

Heck no son. You don't drive a damn civic. If you expect better than 20 out of that caar... sell it now.

[stanglifemike]

Originally Posted by Jucostud Heck no son. You don't drive a damn civic. If you expect better than 20 out of that caar... sell it now.

Haha, +1

[Miggy #23 RF]

i get on average 22 mpg. you probably just need a little tune like cleaning your air filter, new plugs, and maybe a new fuel filter. that might net you more mpg.

[TheUNZippee!]

Seafoam.

[G.T. Rags]

Originally Posted by zigbigadoru nope its stock 3.27 gears. how is 20 good considering i get 17 in the city? im pretty sure our cars are rated at like 27 highway arent they?

i don't even think the 3v's are rated at that.....

try 18/21 on a good day

[TheUNZippee!]

Dan is about right. The 3v S197's are rated at 26 or 27 hwy. The older GT's are not going to get that. But you should probably be a little higher than 20, perhaps 22 or 23.

Another possibility is that your dad was a little off in his calculations. If you want to be positive, check it for yourself. One Sunday, jam the tank full of fuel, go out for a 50 mile cruise, come back, and jam it full again. Then do the math.

[G.T. Rags]

Originally Posted by TheUNZippee! Dan is about right. The 3v S197's are rated at 26 or 27 hwy. The older GT's are not going to get that. But you should probably be a little higher than 20, perhaps 22 or 23. Another possibility is that your dad was a little off in his calculations. If you want to be positive, check it for yourself. One Sunday, jam the tank full of fuel, go out for a 50 mile cruise, come back, and jam it full again. Then do the math.

i beleive the NPI gt's get worse mileage then the PI GT's do to a better flow. I know that once i did my PI/Gear swap i picked up about 2-3mpg....

[TheUNZippee!]

And that brought you to the 20 you mentioned up there^, or you now get like 22-23?

[G.T. Rags]

Originally Posted by TheUNZippee! And that brought you to the 20 you mentioned up there^, or you now get like 22-23?

most i have ever gotten was 20mpg doing 70 in 5th with 80% on the highway. there were a couple of hard pulls though, so I might have been able to squeeze 1mpg more out of her.

when i was stock i was lucky if i got 15, but it was all in-town driving and not more then 5 miles a shot

[TheUNZippee!]

Ah ok gotcha.

[kcrown98gt]

when i had the 3.27s i got about 23 at 50-65 mph but now with 3.55s i get about 20...you realize your car is a v8 right these aint no ford escorts or jap rockets

[blackbirdl98]

I get 24 mpg on my 98 gt with 373 gear if iI stay at 55-65,any faster it gets worse . I agree with 327 gear it should get better than 20 mpg, but it wont ever get 27 mpg!!

[MikeD05GT]

20 is about right dude...thats about what i get on highway...and about 13-14 in town