Gas mileage with handling option - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

DCM · 03-21-2007, 17:39

I intend to order a new Grand Marquis when the 2008 models are available and would like the handling option. I hear that the differentials are different with a lower geared rear end.

Does this option reduce the gas mileage by very much?

Thanks

Nathan in MN · 03-23-2007, 17:12

Depends. What kind of driving do you do? If it's primarily city driving, then a lower rear end will greatly improve your fuel economy. If you do more highway, then a rear end with less reduction will be a better choice.

That said, the fuel mileage will be fairly decent regardless. My dad has a '96 Crown Victoria (basically the same running gear) with 3.27s and it gets 24 mpg highway with the AC blasting. I'm not sure what rear axle ratio the HPPs use, but it's probably either a 3.27 or 3.55 (3.55 is more likely). Bottom line, if you're concerned about highway fuel economy, don't be. You should be able to get mid-20s at least. If you're concerned about city fuel economy, you'll be better off with the lower geared rear end anyway.

DCM · 03-23-2007, 18:33

Nathan

Thanks for the response. That was what I was hoping to hear. The rear end with the dual exhausts and larger engine has a 3.27 I think. The smaller engine with single exhaust is a 2.xx ratio.

If it is only a mile or two per gallon less, I will go for it.

Thanks again

Nathan in MN · 03-26-2007, 07:24

The other ratio would be a 2.73, and the car would be a total dog with those. I have 'em in my '89, and it's not even enough ratio in overdrive on the highway. I'm switching to 3.31 gears this summer.

BigJon · 04-04-2007, 23:13

they all have the same size engine too. :)