Is it normal for MPG to greatly decrease after 70+ mph

FWIW, I get just short of 21 mpg running 70 mph on cruise feeding the 4.0L and Automatic.

Over that.....mpg tanks. Also, figure out the gain in time.......

Simple example: Drive 70 mph, you cover 70 miles in 1 hour. Drive the same 70 miles at 80 mph, you cover the distance in 52.5 minutes......you arrive 7.5 minutes earlier. Really its not much of a gain, especially in the typical 10-20 mile run. Generally, traffic will disturb a steady speed.

 

The air dam isn't on the hood...………………….. its under the front bumper. The OR doesn't come with one and the Sport does

 

Then why do we all need to drive so fast? Being slow is really dangerous, especially on the morning run. Coming home is less stressful.

 

Ohh... And the OR can't have one because? Not that I want to do modifications for gas mileage.

 

Outside of cities, I roll in the RH lane on cruise set at 70 mph. In cities, cruise is off, I run with the traffic.

 

I got 21.1 according to the trip meter, this morning. It gets much better in the summer. But I find going a little slower (than the 75 MPH speed limit) results in gas savings, not that much time loss, and I'm not angry at traffic since I'm not catching vehicles at the same rate. Plus, if I'm running behind, I have a little room I can use to step it up if needed.

 

This is so true. I like driving quick but I hate to admit that being on the lower end of the average speed is much less stressful then being on the upper end and the loss of time is not that great.

 

I travel 140ish miles a day for work and yes not using cruise helps mpgs . I try to keep it around 65 to 67mph

 

Mpg wise, manual sucks going faster than 65-70. I can get 24.75 in the summer driving 55-60 hah.

MTs have 4.30 diff gear ratio so they run higher rpms on highway than ATs.

 

Radar cruise or steady speed cruise? I find the opposite to be true usually, but that is on the set speed cruise.

 

No you don’t. That thing might give you .5 mpg if you are lucky.

 

A multitude of factors come into play. I'd assume by this point you're past the break in. However, short trips kill MPG. Over 70 MPH kills MPG, especially in 4x4 pickups. Also, colder weather will cause the computer to adjust the fuel mixture, and not to mention winter gas is worse for MPG in general.

As for your other comment about speed, having driven in Detroit I can personally attest that no, you do not NEED to go 80 MPH. Especially if you find yourself on 10 where the speed limit is actually 55.

 

because its tailored to the off road crowd so it doesn't come with one to have a better approach angle for offroading. it can have one it just doesn't because of that

 

Nah, I took it off and got 1mpg and put it back on and get 1.7. your math is off

 

.7 mpg?

 

Yup, your MPG will be better in spring/summer. Wait till it snows and you are in 4x4 for a full tank... 10-12mpg here we come

Air dam is the part under the bumper. It doesnt come on OR's or PRO's. it increases mpg by about 5% on the highway.

 

One thing I've learned from TW is many people are FOS when it comes to mileage.
You'll see someone with a stock 2wd auto 3.5 averaging 21mpg at 55 and some yahoo that claims 28mpg average at 85 mph with his full skids/bumpers/lifted 4.0 on 35's...

 

I agree.

Adaptive CC = bad MPG
Manual CC = Can be great if <72 MPH

At least that's my experience.

 

Also depends on conditions. Hilly terrain and CC will hurt mileage.

I live in the middle of nowhere, no traffic, pan flat and straight roads, and have a manual. I haven't done the math but I can't imagine I'd get worse mileage using CC than without under these conditions.