In 1980 mom and dad bought a 1980 Oldsmobile Cutlass with a 5.7 diesel, dad had high expectations, on a trip, cruising along with the rigs, he wasn't impressed, so the tech at the dealer came out and hooked devices to it and took dad on the Hwy, drove it the speeds dad made on the trip, then drove it the speed limit, which was 55 MPH, the car was getting 34 MPG at 55. It is well known anything past 55 MPH decreases the mileage, thats why when the gas crunch was put on us, that limit was set, not for safety, but to save fuel. Gas engines have things working against them, they are not efficient, compared to diesel, it's just a fact, add ethanol to the fuel and they decrease further, the twist it, by the time the gov MPH standard is reached, they plan to increase the ethanol content 5%, and lose what they have gained.
Aerodynamics has been thrown out the window and replaced by inferior material to lighten vehicles, because everyone wants a big 'truck' and demand it get better mileage, park a 70's pickup next to the junk today, you'll see, it's not for loading, my grandfather put 2 tons in his F-100 repeatedly, had a trailer with logs behind it, the tractor that pulled him out of the woods did wheel stands, and he went across town.
Driving slower saves fuel, but in today's hurried society, it's a good way to get you killed.

 

wow somebody finally mentioned the 70s fuel crisis. I was just a kid when the 55mpg thing came to the US, but remember it well. I have checked mileage with every vehicle I have ever owned even checked other people's mileage for them if they gave me all the info from fillups.


55mpg is the sweet spot , here in the great white north we call it 90km/h.


if you are towing a trailer its all about your powerband of the engine, work it too hard you lose mileage, rev it outside its powerband you lose too.


when broaching the 55mph range aerodynamics become a bigger factor in fuel consumption, even aerodynamics of the underside of the vehicle come into play.


if everybody slowed down to 55mph , injuries in cars would increase and deaths would decrease. smaller lawsuits , cheaper insurance, less dependency on oil producing nations if less oil is needed.......................


its a win/win/win/win plan.enforcement would be a nightmare

 

Like I said, everyone is in a hurry, 55 is reserved for rural roads posted with 45 MPH signs, the hwy, truckers coming off of hills, their minimum speed is 80, often you'll have them inches from your back door in the slow lane, they intimidate people into driving faster, no lane is safe for those trying to maximize mileage by driving slower!

 

I was 22 years old in 1974 and I HATED the 55 mph speed limit.

If anything, I would go for a 55 mph limit for vehicles over 4000 lbs or whatever other arbitrary standard could be made to work, and would sooner drive a Prius at 80 mph than a bigger vehicle at 55. My gas mileage would still be better.

There are numerous studies that show that speed (within, say a 70 mph speed limit) is not THAT big a contributor to highway deaths. It is a VARIANCE in speed that causes accidents. (and of course this goes against my proposal above)

Today's vehicles, in general, get better gas mileage at 70 than 1974 "early smogger" vehicles did at 55 mph. Big cars and trucks in 1974 got 12 mpg...

People's time has value (and in fact time is the ultimate currency), and slower speed limits waste a LOT of time. Lower limits to 55 and I'll bet that many more people will spend that time talking or texting on cell phones, eating, etc. because they won't have the time to stop at a restaurant or rest stop.

Slower speed limits were despised in their day, and I despise the idea of slower speed limits now. Again, I'll buy a Prius if I have to in order to drive fast.

George

 

Not to get into too big of a political debate, but that sounds like the government over regulating. It is not a Win/Win if it takes away peoples choice. If it does the people lose. Government getting involved tends to mess things up more than help. Plus it creates a society of victims who are always looking for a someone else to fix their problems and someone else to blame for their problems.

If I want to spend my $ to purchase the fuel to drive 70-75 mph then that is my choice. Some one else can pick to drive slower and spend their $ on something else. I am not saying there should be NO regulation on speed, but in general the Government continually over steps its bounds and messes things up.

As far as the "Purchasing Oil" debate, we currently have the ability to produce all the oil be need locally, we just choose not too. The whole fossil fuel thing it just people trying to use scare tactics to make an issue so they can solve it and look like a hero.....all politics.

Okay, I am getting off my soap box

With that being said I have recently chosen to slow down to the 60-65mph when ever I have the time so I can have more $ to play with my track car......which gets 9mpg at 100mph+

 

The truckers coming off a hill doing 80 are those "junior space cadets" fresh out of driving school. And they're on your *** cause they've overheated their brakes and cannot slow down. (cause nobody bothered to teach them how to descend a mountain pass safely) So do yourself a favor and move over into the fast lane and speed up. You may as well get used to that happening cause with the company policies of today, it rare to find a truck driver with over 5 yrs. experience under his belt. Dinosaurs like me (37 years and about 4 million miles) are the rarity today. And I'm thinking hard about another line of work to tide me over the next ten years till retirement with the BS the companies are dishing out. They're not interested in experienced drivers, only trying to mitigate their liability in the ever increasing accidents caused by the inexperienced drivers they're hiring to hold the steering wheels in their trucks. The only thing taught in the driving schools today is how to shift gears (and even that is taught the wrong way) pretripping and to back up. As for them going around you, they're likely prohibited by law from using the other lane. So you see, you're using the only lane they can use.

 

That's just it, "Arbitrary" is just arbitrary and has no basis in fact. Mixed speed limits on the same stretch of road is a dangerous proposition for everyone. There's no reason that the limit can't be instituted for all vehicles. I can recall the limits of 30 years ago. With the limits in most states today, law enforcement has much more time to go after the real criminals instead of acting as tax collectors. And professional drivers can focus on things other than watching out for those tax collectors behind a radar gun.

 

I'll not be intimidated by anyone, but one day one of those trucks is gonna get a few 45 caliber holes in it, I don't like being put at risk because someone is in a hurry, I watch them, you have to hit the brakes to overheat them, these guys are pushing everything they can get so they can go up the next hill fast. I drove for quite a few years due to the distance between familys, and in that time I got a view of truckers actions, they believe since they make deliveries, they own the roads, and 4 wheelers, they like to call us, we are in their way, and would be best if we stayed off of the hwy, amazing what you hear on the radio, yeah, I believe truckers should be harassed by the cops for a while.

 

Yep, it had nothing to do with safety, the 55 limit was to conserve fuel, even todays vehicles drop off over 55, they could get over 40 MPG if they drove 55, you can not cross out aerodynamics, car manufactures focused on it in the 80's and 90's, you heard it constantly, look at the 97 F150, now look at pickup trucks, they back slid.

 

wow this went way off the rails.................


back to the mpg VS speed experiment.


I had a brand new 96 F250 diesel 4x4 and back in 1997 I was towing a load of southern parts and a 79 Bronco on my trailer back from Texas.
first couple tanks we were stopping at wrecking yards and winding our way home on secondary roads never above 60 mph, but lots of stops and low speed driving. this portion of our trip, I was averaging 19-19.5 mpg every tank. when we were running out of time and had to hurry home, I pushed the truck at a steady 75mph on interstates other than food and fuel stops and we averaged 13-13.5 mpg rest of this trip.
that was a BIG difference.
the load was anything but aerodynamic, 1 69 8' bed on its end , 1 shortbed 79 on its end, and a 79 Bronco w/o glass behind it.


As for the trucking industry, I work for a Canadian trucking fleet as a mechanic and it was bought over a year ago by a large US trucking company. we are training our own drivers, and paying them as they train. most of them pass but some flunk out. we have many experienced drivers and they are very frustrated with Satelite systems and many will retire early because of it.


quality truck drivers is going to be a problem, for some companies it already is. even good truck mechanic apprentices are getting hard to find. we are lucky ,3 licenced mechanics w/3 solid apprentices in the shop.


I love fixing them , sure as hell wouldn't want to drive one

 

And you're going to be the one causing the next major accident. And the one going to prison for a shooting rampage. There may be some aggressive drivers out there, but they're far and few between to day. There are far more inexperienced drivers than aggressive ones. And next time you go to the store, think about how the products you purchased got there. ALL of it was delivered by a truck driver.

 

I will be interested to see what I get while towing. We are looking at getting a travel trailer for the spring. Just got a call from my family in Texas saying there neighbor is selling theirs. It is has all the features we are looking for, so I may have another road trip in the near future.

I would prefer to have some shorter shake down trips towing the trailer before anything longer, but It looks like the maiden towing voyage may be a 20hr 1300 mile trip........

I am consistently between 17-18mpg running 60mph unloaded (16.5mpg running 65mph). I am hoping I can get in the 12-13mpg range towing the trailer on relatively flat ground. I know it will drop some more in the hills.

 

Perhaps you failed to understand what I said, if you put my line in danger, I Will put you down, and it is perfectly legal.

 

Ummm, no it is not legal to shoot another driver in a road rage situation. I know of no state law that says otherwise.

 

I can protect myself, it is legal, you obviously know nothing about it as you are thinking it is a road rage incident, I am talking about being purposely run over, there is absolutely nowhere to go in that situation! So give it a rest, you don't understand it!