I'd like to avoid a collision!

October 24, 2008 6:50 AM

Driving etiquette Filter: On a two-lane limited access road, when would the left lane be considered thru-traffic lane versus the passing lane?

I know that there isn't a hard and fast rule, just wondering about a rule-of-thumb type driving etiquette as well as expected motorist behavior, so I don't get into an accident.

Where I'm from, the limited access roads are usually interstate highways, with two lanes of traffic each way. So the right lane is the regular speed lane, and the left lane is the passing lane. Entry onto, and exit off of, the road only occurs every 10 miles or so, if that. And traffic is usually minimal, so using the left lane as a passing lane makes sense, because there isn't enough traffic to fill up both lanes. And when you saw cars exiting or entering, you moved over to the left lane to give them room, then got back into the right lane. And if you had a slow car, you simply passed them.
Life was good.

Unfortunately, I now find myself in perpetual traffic hell, known to some as New Jersey. Here, the limited access roads have on/off ramps practically every mile, sometimes even more frequent than that. Many are in a clover leaf pattern, where the entering car has to merge onto traffic in a very short amount of space while navigating the cars that are driving through, and the cars that are exiting. Also, the traffic is very high, such that both lanes are usually filled up with cars.

Given this situation, do people assume that the right lane is for exiting/entering and left lane is for thru-traffic? Or that the right lane is for entering/exiting/regular speed cars, and the left lane is for cars going above the speed limit? Or, do people really expect that the left lane is the passing lane?

Also, if there is a left-lane exit, is the left lane still the "above the speed-limit" lane?

I'd love to hear from people who have driven in these high-density situations that I'm describing, and have survived with their sanity in tact.

Thanks.

posted by jujube to travel & transportation (9 comments total)

Depends on the state, but in general: never. It's always a passing lane.
posted by Grither at 7:06 AM on October 24, 2008 [1 favorite]

And as for NJ (having lived there most of my life), I can tell you that most people don't know/care that it's a passing lane, and pretend like it's a fast lane or some such nonsense.

Traffic wouldn't be nearly as bad if more people actually learned the rules of the road before they were given a drivers license.
posted by Grither at 7:07 AM on October 24, 2008 [2 favorites]

In the Midwest where I'm from, the law is that you're only supposed to use the left lane for passing, and there is no such thing as a "fast lane." Regardless of the law, this is how it works in practice on two-lane roads:

- Average speed for the left lane is 8-15 MPH over the speed limit. If you're going slower than that in the left lane people will tailgate and/or pass you on the right. Average speed for the right lane varies a lot but is usually slower than the left lane.

- In light traffic, people stay mostly in the right lane and use the left lane for passing.

- In heavier traffic, most people who use the left lane get in it and stay there until they exit.
posted by burnmp3s at 7:15 AM on October 24, 2008

Seconding what Grither and burnmp3s say: people treat these highways like they're urban roads. I was raised driving in Texas (slow traffic keep right/left lane for passing only) and came home at the end of last year after four years in New Jersey. Driving patterns are just different. It took me a while to adjust, and I eventually did, but I never stopped bitching about lousy Jersey drivers. (Although I'm sure all my fellow MeFi drivers in NJ were perfect!)

I now live on a semi-suburban highway outside of Austin (360, for Texans) and see some of the same behavior here. It's annoying as all get-out and I wish people would drive friendlier.
posted by immlass at 7:34 AM on October 24, 2008

Twin Cities, Minnesota has a bunch of left entrances and left exits. In heavier traffic, you'll probably be obligated to drive in that left lane just to be ready for your exit.

Example: 35-W south out of downtown. Leftmost lane eventually turns into an exit-only lane to eastbound MN-62, which takes you to the airport. Locals know this, and airport-bound traffic tends to sit in that lane, especially if it looks like opportunities to merge into that lane will be slim further along the highway.
posted by gimonca at 7:57 AM on October 24, 2008

by two-lane you mean 'two lanes each direction', right? Those are called 4-lanes out here, btw.

In open country freeway driving, the lane choice works like this: left lane is for passing, right lane is for normal driving (regardless of speed).

Whenever I drive through e.g. Minneapolis, it seems to work out well to use the right lane for when you want to get on/off and the left lane for through traffic (note that "through" does not imply travelling @ the speed limit!). In fact, I believe there is signage to that effect on I-35/I-94 (the green overhead signs). The trick is to merge into the right lane far enough away so that you don't end up cutting people off trying to get to your exit from the left lane. (or, what burnmp3s said)

That driving style is really only used in moderate traffic, though. If I'm going through there in an off hour, I see the 'left-pass, right-travel' style more often. In heavy traffic, it doesn't really matter because no one is moving anyway.

If you think about it though, the 'left-through, right-exit' driving style is really the same as the 'left-pass, right-travel' style. Everyone in the right lane is going slower, presumably because they have an exit coming up shortly, and are (possibly) making room for other drivers merging into traffic due to the short distances between exits. Therefore, you are passing a whole string of cars at once, instead of the occasional pokey driver.

as for the 'Left Exit': typically, if there is room, they will also be 'Exit Only' so that you can go slower without being rear ended. This may not be the case for you, though.
posted by ArgentCorvid at 8:24 AM on October 24, 2008

Keep right except to pass (left if you're in the UK, Japan, Australia etc). So simple until it gets complicated.

My approach is to take my driving VERY seriously. If I'm in the right lane and I see a bunch of cars merging in, I move left. If I'm in the left lane and somebody's coming up fast, I move right. This means constant use of turn signals, rearview mirrors, over-shoulder checks. And don't fucking tailgate!
posted by philip-random at 9:51 AM on October 24, 2008

Just another datapoint. I've lived (and driven) in rural Missouri, Philadelphia, and now rural Washington.

In light traffic, most everybody stays on the right, and passes on the left.

However, in heavier traffic, people tend to stay in the left lane much longer. This is, in my opinion, not a separate behavior but an extension of passing. Invariably, the people in the left lane are going much faster than the people in the right lane. On I95 in Philly for instance, the speed limit is 55mph. The right lane tends to go about 60mph, and the left lane closer to 70-75mph.

With these speed differences, with enough traffic, if you're one of the fast drivers, you physically can't drive in the right lane until you come up behind somebody and then smoothly pass them. There's simply too much congestion. In Philly, the space between cars was often only three or four car lengths, making it impossible to get back into the right lane in any reasonable period of time while maintaining something resembling safety. So, instead of trying to shift lanes constantly, you just chill in the left lane. It is, however, completely and absolutely unacceptable to go the speed limit in the left lane--you must exceed it by a healthy margin.

Now, you can argue whether or not it's acceptable to exceed the speed limit by 20mph. But, if you are going to do that, I'd far prefer you stay over in the left lane instead of weaving in and out of traffic trying to subscribe to a strict notion of traveling/passing.

This all breaks down over in Seattle, though. I've never been someplace with such fucked up traffic patterns. And I drove in Paris.
posted by Netzapper at 12:34 PM on October 24, 2008

I lived in LA awhile, and learned how to drive that style. I have also lived in Germany, and learned proper Autobahn driving. LA is more sensible.

Making a fetish of left-lane pass-only is not safe. Lane changes are dangerous, and the more you change, the more danger to yourself and everyone around you. You see Germans passing left, then going back to the right immediately, in order to travel about 10 seconds before going back to the left to pass. Insane, but correct, and stupid.

In LA, it's different. Commuting from Long Beach to downtown, I discovered the Safe Way: Go to fast lane, drive at the prevailing speed, and only leave that lane when you're ready to exit, or you must get out of someone's way that is going much faster (amazingly, it does happen sometimes). Those other folks are creating delays and danger with their constant lane-changing habits.
posted by Goofyy at 9:01 AM on October 27, 2008