Commute Choice: 40 mph (with stop lights) or 30 mph steady flow?


#1

My daily commute choice is between two different paths (10 miles stretches) that are parallel to each other.

Street #1: 35mph (40mph with flow of traffic). Downsides: Lots of long stop lights. Very busy road; lots of businesses on both sides of the street. Traffic accidents are common. Upside: 5th gear for a mile stretch feels so nice.

Road #2: 30 mph limit. Someone is always driving 30mph, and traffic can slow to 25-27 mph. However the traffic flows better than Street #1. The overall travel time is a tie between Street #1 vs. Road #2. Downside: driving 27mph-30mph for 10 miles is frustrating!

Does driving at 30 mph put more wear-n-tear on a car versus 40mph? Will driving at 30mph going to lower gas mileage?

Which of these two commutes would you choose?


#2

I’ll take steady 30 mph over 40 or even 50 mph stop and go any day, both for time and gas mileage considerations. My car and motorcycle have no problems running high gear at 30 mph if I’m driving a steady speed and not accelerating. It’s the stop and go that kills your city gas mileage, not the low speed limits. It’s also the stop and go that wears out your brake pads so soon when you do mostly city driving.
Don’t underestimate the damage that going zero mph for a minute does to your average speed.


#3

Note that a hybrid or electric car will do better at stop and go, as much of the energy used for braking is recovered and used for starting. That is, as long as you make gradual stops. But not all the energy is recovered, just some of it.

But even then, I’d vote for the slower steady speed.

Note that the best gas mileage is obtained at the slowest speed you can drive in your highest gear.


#4

Even hybrids get better gas mileage at a steady speed than they do in stop and go. It’s just that stop and go doesn’t kill their gas mileage as badly as it does for a vehicle that can not recover kinetic energy while decelerating.

When I’m driving my 5 speed manual in city traffic, I’m covering a lot of the distance coasting towards the next red light in neutral. Usually, it turns green before I reach it and than I can put my car in second or third and re-accelerate, using very little braking. This results in city gas mileage that approaches that of hybrids.


#5

Just drive the route that lets you arrive at work with less stress and allows you to do the job you are paid to do.


#6

I’d take the route with the best bagel shop.


#7

One five to ten minute stop to buy a bagel, pee, or whatever and you’ll lose more time than you can ever make up by driving 80 mph the rest of the trip. Stops absolutely murder your average speed and unless you are going a long way, speeding will seldom gain that time back.

When I’m pressed for time and there are two routes with similar GPS estimated times of arrival (ETA), one a high speed limit highway and the other a more direct route on a low speed limit rural road, I’ll take the low speed limit rural route. Driving 60 on a road posted at 50 will gain you 12 seconds for every mile traveled. To gain 12 seconds per mile traveled on a road posted at 70 mph, you would have to go 91.3 mph.
You’ll get in a lot less trouble if you are caught going 60 on a 50 mph road than you will getting caught going 91.3 on a 70 mph road, in fact you probably won’t even get stopped and if you are, you probably will get off with a warning.

I’m constantly amused that the same people who drive like they are on their way to a fire don’t run as fast as they can on their ways to and from their car’s parking spot.


#8

As others have eluded to, don’t even worry about how each route affects your vehicle. You’ll never experience degraded vehicle wear from either choice.

I’d follow the previous recommendations about bagel shops, being able to pee, or less stress.


#9

I get to work early by simply leaving early. In my case, the time gained by leaving earlier is compounded by lighter traffic. Fewer red lights that take two light cycles to get across and stuff like that. Less stressful too and it’s nice to be at work early enough to enjoy a cup of coffee.


#10

Forget about wear on the car! I would take the route that is easiest on the DRIVER.

We live in the extreme SE of our city and many activities at the University are at their NW location. Depending on the day of the week and time of day as well as the weather, I take the easiest route. Least “wear” on myself.


#11

10 miles at steady 25-30mph?
Talk about mind numbing.

I’d take the stop and go if for no other reason than to try and shoot for some record of hitting lights along the way and a CHANCE to do better.

Actually, faced with those choices, I’d probably ride my motorcycle everyday. With the acceleration capability, I could easily do it in less time than the car. It would be the least boring, shortest time and least amount of fuel consumed…win, win, win.


#12

Find the third, more interesting and faster route, or take one until you tire of it and switch to the other.