Average cruising speeds on freeways in your area/state

[I-55]

My experience is as long as you don't stand out you'll be fine.

[GaryV]

I drove I-96 from metro Detroit to Grand Rapids and back on Saturday.  I had my cruise set at 75, and got passed more times than I passed others - roughly 2:1.  But those that were passing me were typically within 5 mph of my speed.  So with those that were slower than me and those that were faster, I'd estimate the median speed to be somewhere between 75 and 80, probably closer to 75.

[kphoger]

I've been cruising at the speed limit lately, most I've done is 5 over and to be honest it doesn't get you that far to go that much faster. I was coming over the Holland Street Bridge in Saginaw earlier at 30 mph which is the speed limit and a guy blows past me at about 50 or so and the light at Michigan was green so I knew it was going to change soon so I slowed down and this car raced up to the light and it changed before he got there so I just rolled up to the red light thinking that got you far plus you used up more gas to get here.

Depends. On a surface arterial, maybe. On a long distance interstate trip? Driving 80 or 85 mph vs. 70 mph for hundreds of miles can easily cut an hour or more off.

Heck, yeah.

On a 700-mile trip on 70-mph highways, just going 8 over the speed limit saves a whole hour.