was wondering what kind of gas milage you guys where getting 38-40 inch tires and what gearing you have. thinking of making the leap to 40s, but it is still my daily driver.

 

Fortunately you have D44 front so you can readily go to 5.38s but I didn't see a Hemi or SC in your profile. So if it is your DD, then it comes down to your driving style and your tolerance for pain on the road.

Look at the RPM vs tire size charts FAQ in this section and find the RPM at your typical freeway cruising speed. Then look at the Power and Torque curves for the 3.8L and see where you fall on these curves.

In rough terms, the torque value will determine your ability to sustain your selected speed and the HP will determine your ability to accelerate from steady state.

Your MPG, braking and handling will also be affected, so unless you are conservative driver on the road, you may want to stay within the 37-38" range.

 

That's backwards, for an easy explanation I like to think of Torque as a hammer and Horsepower as a come-along.

 

Agreed, for the 3.8L it's like a tack hammer and a ratchet strap lol

 

Yeah, agreed. Maybe one of those take your eye out bungie cords from the dollar store.

Also, in an attempt to get back on topic, I don't think 5.38s are a tall enough gear for an automatic and 38" or larger tires.