Was told I am dangerous, I disagree

[Scout26]

4 lanes total, or 4 lanes on your side?
If there is very little traffic and you're staying out of the fast lane (or accelerating in the fast lane to pass slower traffic in your lane), then I don't see any issue anyway.  Semi trucks rarely go 75mph+ anymore, and they're all over the highway.  What about gravel and cement trucks?  People towing campers?
Your co-worker is an idiot.

This.   And I'm right there with you.  It seems like the Outback with flat four is more "comfortable" cruising at 65mph as opposed to 70-75mph.   I generally try to keep it at 65mph when I go to Indy, for the same reasons.  (Better fuel economy, doesn't feel like I'm stressing the engine or me.)  Trucks on I-65  are limited to 65mph, so I generally end up between or behind a couple of trucks.  I stay in the right hand lane, unless I'm passing and then I'll bump it up to 70-75mph get around and then get my butt back over in the right hand lane.

And since your on the interstate in Montana, I'm sure there's nowhere near the traffic that there is on I-65 between in Indy and Chicago.  

So set it a 65mph, stay in the right hand lane, unless passing, and when passing, bump it up to 70-75mph (or higher) to get around them and then get back over.  

Your cow-orker is a moron.

[roo_ster]

To me, it is more dangerous driving with the pack.  With no one around me, I don't have to worry if I inadvertently drift a little or if other cars around me make sudden moves.  I get more nervous with other cars around.

Plus, IMO, many of the drivers who herd with the group are the type that hit the brakes automatically if anything happens.  

"More dangerous than if 41magsnub ran with the herd." was metaphorical.  To be literal, "maintaining the same speed that roughly 85% of drivers maintain."

And, yeah, if there is no one on the road, it doesn't really matter.  For my part, I am more likely to fall asleep going less than hte limit.

[brimic]

It seems like the Outback with flat four is more "comfortable" cruising at 65mph as opposed to 70-75mph.

I have similar car with same engine- they do seem to suck a lot more gas at higher speeds. I think the little gauges they put in those cars guilt you into driving slower. I typically get around 29mpg with my commuting (mixed freeway/urban/city), and get all anxious when the MPG meter falls into the 27MPG range, but in reality it doesn't mean all that much. Funny thing is, my last car had a big V-6 in it and I didn't care much if I got 24 mpg or 21 mpg between fill ups. If it fell into the upper end, I just took that as a bonus.

[KD5NRH]

I think the little gauges they put in those cars guilt you into driving slower. I typically get around 29mpg with my commuting (mixed freeway/urban/city), and get all anxious when the MPG meter falls into the 27MPG range, but in reality it doesn't mean all that much.

This is why I prefer to use the OBDII reader and the Torque app to track my MPG; I can get instantaneous and trip average on the same screen.  I'd like to have a ~5min running average too, but haven't seen an app that offers it.  Sure, instantaneous drops to ~20 climbing a hill at 75MPH, but then going down, it's at 60+.  As long as trip average stays well above 30, I'm happy.  For interstate driving, it's rarely under 36 even with a strong headwind, and 39.4 (38.9 as calculated by topping off the tank and dividing by the miles traveled) is the best I've sustained over a 100mi run.

[Brad Johnson]

If there's traffic, even light traffic, travelling at well above or below the posted limit introduces a marked discontinuity in smooth traffic flow. Anything that requires the majority of other drivers to make an unplanned large correction in speed or course is, by definition, a danger. To what degree is dependent on traffic density, road type, conditions, etc.. There's also the element of vehicle size. A tractor trailer driving 65 in a 75 is easily spotted from a distance. It gives other drivers time to anticipate and plan (if they aren't too busy texting). A small coupe or sedan is easily lost behind the silhouette of preceding traffic, increasing the likelyhood of panic-response detection and evasion.

If the road is deserted and you are your own 85th percentile, drive whatever speed suites your fancy. Otherwise don't be surprised when drivers trying to blend in with the flow get a little miffed when they have to dodge you.

As to speed-related economy, it's a given. Air resistance increases as a square of speed. Ten mph might not seem like much but when you consider it's 15.4% increase in speed from 65 to 75 the difference in economy-killing drag is significant.

Brad

[Tallpine]

If there's traffic, even light traffic, travelling at well above or below the posted limit introduces a marked discontinuity in smooth traffic flow. Anything that requires the majority of other drivers to make an unplanned large correction in speed or course is, by definition, a danger. To what degree is dependent on traffic density, road type, conditions, etc.. There's also the element of vehicle size. A tractor trailer driving 65 in a 75 is easily spotted from a distance. It gives other drivers time to anticipate and plan (if they aren't too busy texting). A small coupe or sedan is easily lost behind the silhouette of preceding traffic, increasing the likelyhood of panic-response detection and evasion....
Brad

Why the heck do you even think they build multi-lane highways 

So that the faster traffic can go around the slower traffic 

If you can't see a flipping car in front of you going 10 mph under the speed limit, then you are the problem 

If there is other traffic between you and the slower car, then seeing them change to the left lane to pass might be a clue ..... 

[KD5NRH]

If you can't see a flipping car in front of you going 10 mph under the speed limit, then you are the problem

Twice in the last week in this county, people have rear ended farm equipment on highways with excellent visibility.  Never assume any driver can see past their hood.

[Tallpine]

Twice in the last week in this county, people have rear ended farm equipment on highways with excellent visibility.  Never assume any driver can see past their hood.

Which is the fault of the driver running into the other vehicle.

Lots of farm equipment out on the 2-lane during the summertime here.

[Boomhauer]

Intentionally creating a condition which impedes the general flow of traffic, especially on something asheaviky travelled as an interstate, is inherently unsafe. Either go with the flow or find roadways which support yourr self-imposed speed restriction.

FYI...
650 miles @ 31 mpg = 21.97 gallons
650 miles @ 27 mpg = 24.07 gallons

Congrats, you save a whopping twelve bucks, and in the process you place every other driver in peril. Just say no.

Brad

Then go tell all the big rigs to get off the road then, because these days most of them are governed to around 60-65 by the companies that own them for best fuel efficiency.

[lupinus]

If its not much traffic have fun. However when there's enough traffic someone can't just cruise into the other lane pretty much at will them I'm going with don't block tge flow of traffic, at least up to the speed limit.

In short if there's no reason for someone to have to slow down or jump on brakes do as you please, within reason of course.

[Brad Johnson]

Why the heck do you even think they build multi-lane highways 

So that the faster traffic can go around the slower traffic 

If you can't see a flipping car in front of you going 10 mph under the speed limit, then you are the problem 

If there is other traffic between you and the slower car, then seeing them change to the left lane to pass might be a clue ..... 

I disagree. In a multilane full of traffic there are plenty of ways to lose a smaller vehicle in the crowd ahead. Anyone who drives busy multilanes regularly knows this all too well. Besides, it's a bit selfish and self-serving for a driver to expect the world (in this case, every other driver on the road) should be revolving around them, don't you think? (Edit to add... not direct at any particular post or member. Using it in the generc sense.)

Boom, chill. Yes, I know about trucks. My brother has four rigs that I help with. We're not discussing fleet efficency. We're examining a single event, and motivation versus actual result.

Brad

[41magsnub]

If its not much traffic have fun. However when there's enough traffic someone can't just cruise into the other lane pretty much at will them I'm going with don't block tge flow of traffic, at least up to the speed limit.

In short if there's no reason for someone to have to slow down or jump on brakes do as you please, within reason of course.

Which is exactly what I am doing, per the original post spelled out in extra detail because of folks tendency to jump to conclusions.

[Chuck Dye]

He thinks this is dangerous...

Are you creating a dangerous condition?  No.

Are you endangering yourself?  Perhaps, but no more than usual.  We are all at risk every time we venture forth into the world.

I drive 120,000 to 140,000 miles annually in trucks that are often slower than the speed limit due to power to weight issues, occasionally (NV & AZ) due to company set top speed.  Make good use of your mirrors and do the courteous, but not stupid, thing when you are delaying others.

[Brad Johnson]

... courteous, but not stupid, thing when you are delaying others.

KEY WORD!!
KEY WORD!!
KEY WORD!!

Brad

[Hawkmoon]

If you're speeding up when other cars are around, that's fine. If not, you create a situation where drivers behind you may make risky moves to get around you. 10 mph is a big speed differential.

Under pretty much all traffic engineering standards, "slow vehicle" on a limited access highway is under 40 MPH. 10 MPH under the speed limit, if you stay in the granny lane, is not dangerous at all.

[Boomhauer]

The driver going 10 under the limit is not the problem on the interstate. Slight inconvience maybe, but not a problem. The problems are the people texting, the people doing 45 in a 65 because they are granny-driving, the people who think they are in a NASCAR race and are entitled to drive 95 in the 65 zone and weaving through traffic, the people shooting across 4 lanes of traffic to get to their exit, the drivers who are tired and falling asleep, etc.

[Hawkmoon]

"More dangerous than if 41magsnub ran with the herd." was metaphorical.  To be literal, "maintaining the same speed that roughly 85% of drivers maintain."

So if 85% or other drivers exceed the speed limit, thus breaking the law, we should break the law too?

Sorry, I can't agree to that. Speed limits are maximum speed limits (except for maybe two roads I've seen in my entire life that stated a minimum speed -- 40 MPH -- in addition to the maximum limit). It's not unlawful to drive slower than the posted speed limit. It IS unlawful to drive faster.

[Brad Johnson]

The driver going 10 under the limit is not the problem on the interstate. Slight inconvience maybe, but not a problem. The problems are the people texting, the people doing 45 in a 65 because they are granny-driving, the people who think they are in a NASCAR race and are entitled to drive 95 in the 65 zone and weaving through traffic, the people shooting across 4 lanes of traffic to get to their exit, the drivers who are tired and falling asleep, etc.

Yes, I know. And I agree. That's why I included both under- and over-speed driving as well as allowing for road and traffic conditions when determining if under-limit driving is appropriate. If 41mag has given due consideration in this regard then I have no issue with what he proposes.

Hawk, just because a limit is posted does not automatically make it either practical or safe. Legality notwithstanding, maintaining the same speed as 85th percentile drivers around you is, statistically speaking, the safest way to travel.

Brad

[Calumus]

From what I understand, the speed limit is supposed to be set at the average speed of the 85th percentile. In NJ, that's no where near the case. Group average on Rt.80 is around 80-85, speed limit is set at 65 for most of it. That won't likely ever change just because of the cash the state rakes in. When the feds dropped the mandated 55 nationwide, NJ bumped the limit in certain areas to 65 with the stipulation that ALL fines are doubled in a 65 zone. $130 for a tail light out. That being said, I don't see an issue as long as you're doing what you said you were. My mother on the other hand, insists on doing the speed limit in the center lane. She's adamant that its only the far left lane that's for passing. As a result, she has a constant stream of cars passing her on both sides all the time.

[Hawkmoon]

Hawk, just because a limit is posted does not automatically make it either practical or safe. Legality notwithstanding, maintaining the same speed as 85th percentile drivers around you is, statistically speaking, the safest way to travel.

By the same logic, if 85 percent of the drivers obeyed the speed limit, then by your analysis driving at the speed limit would magically become safe.

I stand by my statement. The fact that 85 percent of drivers routinely exceed the speed limit, coupled with the fact that it is the differentials in speed that can be dangerous, doesn't mean that the one person who obeys the speed limits (which are set according to traffic engineering analyses for safety) is creating an unsafe condition. Rather, it's the 85 percent who choose to ignore the legal limit who are creating the unsafe condition.

[Parker Dean]

Then go tell all the big rigs to get off the road then, because these days most of them are governed to around 60-65 by the companies that own them for best fuel efficiency.

Was just going to mention this. Mine is governed to 65 and I generally run 62 to help ensure the fuel bonus and give me a little headroom for passing if I come up on somebody. Interestingly the vehicles I run up on most often are Ranger pickups followed by mid Eighties Toyota pickups (what few haven't been taken South)

[KD5NRH]

Then go tell all the big rigs to get off the road then, because these days most of them are governed to around 60-65 by the companies that own them for best fuel efficiency.

Funny; every time I get on I20, the big rigs are keeping up at 75.  The problem is that they don't always check lanes very well before moving over to pass the slower traffic.

[Hawkmoon]

How many states have a speed limit for trucks that's 10 MPH slower than for cars? I know there are some, but I don't recall where. I'm sure if it created more accidents than it prevents those states would change it.

[Tallpine]

I disagree. In a multilane full of traffic there are plenty of ways to lose a smaller vehicle in the crowd ahead. Anyone who drives busy multilanes regularly knows this all too well. Besides, it's a bit selfish and self-serving for a driver to expect the world (in this case, every other driver on the road) should be revolving around them, don't you think? (Edit to add... not direct at any particular post or member. Using it in the generc sense.)

Boom, chill. Yes, I know about trucks. My brother has four rigs that I help with. We're not discussing fleet efficency. We're examining a single event, and motivation versus actual result.

Brad

I would say that applies to the folks who think they have a god given right to always drive at or usually above the speed limit and think that everyone else should just get the hell out of the way 

It's not much of a problem in Montana and Wyoming, even on I-80.  But down in Colorado, 99% want to drive 25mph over the speed limit, either on the interstate or on some winding mountain pass with hairpin curves marked 10mph, or in heavy rain on a rutted two lane with several inches of standing water 

So you think I ought to be squealing the tires on every corner or risk hydroplaning off into the Yampa River just because somebody else wants to speed    (not to mention being the out of state driver that gets a ticket)

How many states have a speed limit for trucks that's 10 MPH slower than for cars? I know there are some, but I don't recall where. I'm sure if it created more accidents than it prevents those states would change it.

Montana, for one.  That's why I try to drive the truck speed limit at least.

[Ben]

How many states have a speed limit for trucks that's 10 MPH slower than for cars? I know there are some, but I don't recall where. I'm sure if it created more accidents than it prevents those states would change it.

CA is 55MPH, which can be up to 15MPH less. I actually don't see that many big rigs doing 55MPH in the areas where you can drive 70MPH. They generally (probably the independent guys without a meter?) are doing up to a tad over 60MPH in those zones (with the occasional speed demon doing 70MPH. In my experience though, as a whole the big rig guys are much better on the road than passenger vehicle drivers. Sure, there are jerks, but they seem to be a smaller portion of that population than the general driving population. Additionally, I'm probably giving them a bit more leeway than I do passenger vehicle drivers, knowing that they have a whole lot more vehicle and weight to handle.