Semi traffic and speed

Hay hay hay

Well-known Member
In my last 3 or 4 interstate trips this month, I have noticed a significant increase in semi-18 wheeler traffic (which I attribute to the vastly improved economy), and the speed they are rolling.

Last night late, I was one lonely pickup in a string of about 25 semis. We were all running a steady 75 MPH. I had the cruise set and for one stretch of about 40 miles we rolled along evenly.
In that stretch, a couple semis pulled out and passed all of us. They must have been running 80 MPH. How much HP does it take to do that?

Are you guys seeing the same thing?
 
I like the trucks WHO think they have enough smoke to pull out and go around but they don't and then they plug up all the traffic ! There is a hill out of Wooster Ohio on rt 30 west bound. Long steady grade gets those guys everytime and then I'm stuck behind them after work almost everyday.
 
Edd, Not just HP, but it is Nice, Mostly 500+
But rear Gears, and Slots in the tranny to go to! & OD and Double Overs Slots
Had a Buddy in the Okla. Panhandle that had and Old Pete COE with a Punched out 400 Cummins to 435! W/ a turned around 10 speed. have no idea of rear gears. This old Sow would run 35 to 40 mph in reverse! His old truck had been Clocked and Stopped with a loaded Bullwagon @ 120 mph, Yes, I saw the ticket!
Hope this helps
Later,
John A.
 

If a truck is empty with a low trailer or a flatbed and is geared high 80 MPH is very easy to maintain on the flat with 400 HP. A lot of the newer trucks on the road are running well over 500 HP.
 
This is from Cummins and should tell you what it takes.
My truck is 385 hp from the factory and geared to go 87mph at rated rpm. If everything is perfect it will go just over 80 mph.
a176764.jpg
 
I have almost been sideswiped twice within this last week by 18 wheelers coming over in my lane as I was passing. I ended up on the shoulder honking both times. Getting a little old.

I suspect they are tired or texting.

Gene
 
All trucks are running a bit faster now i think. I see 3 main reasons,
1, trucks newer than 2012 are much more fuel efficient and can run at 70 on less fuel than pre 12's can run at 62.
2, fuel prices are dropping.
3,trucking companies are paying out huge settlements for accidents if they run speed limiters set at less than the speed limits. The lawyers found out that limiting speeds for trucks through laws or governers causes accidents and are adding that to the reasons companies should pay more for settlements.
 
They just said on the news this morning the economy is much better, and with much lower fuel prices, all time traffic records are being broken.
 
That is about what Cummins told us when I was still working. Takes 200 horses to pull 80k at 60mph, level road, no wind.
One batch, thinking 98 models, had Cummins engine display. Fun to watch the instant mileage drop when kick speed up from 60 to 70, or a bend in road changed side wind to head on.
Willie
 
Here in north and west Texas the truck traffic volume is definitely UP. My rating for worse drivers is;
1.rented bobtails (not semis, but still on the road, no CDL, no experience etc.)
2. Oil patch water/brine haulers (junky dirty mud covered trucks, rookie drivers for the most part it appears, big chunks of mud fall off etc)
3. Rockhaulers (paid by the load I assume by the speeds they run)
4. Independents (one truck owner operators trying to make all they can, nearly always running fast.)
Just my 2 cent observations. The big company line trucks are mostly monitored by satellite and seem to follow the limits for the most part. I must add that the fastest running trucks I have ever seen on the hiway were cattle haulers.
 
Dean, This was back in the mid 80s. You Have No Clue to the Bull Wagon Hand I ran with , more or less attempted to stay up with. These guys all had trucks that would run 30 mph faster than ours was!
We Farmed and Ranched, Truckin was an off and on deal for us , so 75mph was plenty fast to get a ticket for our haulin we did.
H3LL! We had a 79 KW Conventional, 36 in sleeper, 220 wb, Silver 430 Detroit Dsl with a RTO 125-13 with 4.33 gears would run 75 all day long, Up hill, Down Hill, All around the Town!, Bull wagon or Weevil wagon!
It it had had 3:55 gears it would have been a 85+ mph truck!
Later,
John A.
 
Well maybe not in the same category, but over time, the amount of commercial truck traffic has increased. Where I live, is a corridor to Vermont and New England, and I see trucks, tractor trailers 24 hours a day.

One of the things that stands out is excess speed. Another is the use of hand held devices such as ones cell phone, with no regard for the distraction. The excess speed is a noticeable problem, click on the link below. I don't recall what the investigation results determined, but we do know that this has become a hot spot for roll overs. There are several others in the area, and it appears that drivers do not respect the rules when they have a load on. I see drivers of heavy commercial vehicles leaning them in turns, and driving at speeds that are unsafe. The accident in the article was an LPG trailer, and in the early 60's one of those did quite a bit of damage in a rural town just south of the accident location. Many people recall what happened then, and this one was like it was happening again. These are 2 lane roads, and I hate traveling them because you have to keep your eyes on every vehicle going the other direction, there have been more head on collisions on this stretch than I can recall, and I have witnessed a few. In the 70's there were red and white bumper stickers that said, "Pray For Us We Drive Route 7" its more true today. On our stretch its always the screech of skidding tires, followed by the loud bang! Law enforcement patrol cars, ambulances, fire department vehicles responding to situations or events are so much more numerous now, when I was a kid it was not very often, now its like the nearby city !

The stretch profiled in the article is a scenic area, but all "S" turns, in the mid 80's they did re-align it better, at a high cost, but there just is no way to deal with it, its a pass between small mountains, before it was worse, and truck traffic was significant then, I cannot recall any of these kinds of accidents for years and years, now they are common and there is no doubt in my mind that its careless drivers.

Years ago, trucks were slow, drivers were more attentive or so it seems, and personally, as I did drive tractor trailers, I was always very careful, more so with a load on. These guys leaning these rigs over in turns, stressing the tires, pushing the limits today, makes no sense to me.

So yes, there is something to this, or so I believe.
Rt 7 accident
 

Like John A said gearing and slots has a lot to do with it at least in rolling hill country. I was pulling a bull rack that was geared high with a ten speed and 4 1/4 Cummins following a couple of other bull racks with the same load on a 55 MPH road. One of the other trucks had a Cummins 350 and 13 speed, Don't know what the other one had, but they pulled away from me because I didn't have any power in the top gear at 55 and dropping down a gear I couldn't do 55. After they got ahead a couple of miles I ran it up to 65 where the power was in tenth and caught up with them. If I would have had a 13 speed I wouldn't have had any trouble at 55.
 
Please tell my 401K that the economy has improved. I have the worst rate of return that I've had in 8 years.
 
My observations are the same as yours. Flat bed o/ops and cattle trucks are the fastest and wildest of all. Sort of the "thunder road"ers of old.
 

Son was a bull hauler for a couple of years, he said bull haulers are called Overweight, Over speed and Over hours. LOL
 
When I pass a truck that is straying over the line or hitting the rumble strips, I try to look in the cab as I pass. A high percentage of the time (if I can see in at all) the driver is on a cell phone or looking down rather than out and ahead. Texting?
Video games? Hope not.
 
(quoted from post at 14:12:51 12/17/14) Well maybe not in the same category, but over time, the amount of commercial truck traffic has increased. Where I live, is a corridor to Vermont and New England, and I see trucks, tractor trailers 24 hours a day.

One of the things that stands out is excess speed. Another is the use of hand held devices such as ones cell phone, with no regard for the distraction. The excess speed is a noticeable problem, click on the link below. I don't recall what the investigation results determined, but we do know that this has become a hot spot for roll overs. There are several others in the area, and it appears that drivers do not respect the rules when they have a load on. I see drivers of heavy commercial vehicles leaning them in turns, and driving at speeds that are unsafe. The accident in the article was an LPG trailer, and in the early 60's one of those did quite a bit of damage in a rural town just south of the accident location. Many people recall what happened then, and this one was like it was happening again. These are 2 lane roads, and I hate traveling them because you have to keep your eyes on every vehicle going the other direction, there have been more head on collisions on this stretch than I can recall, and I have witnessed a few. In the 70's there were red and white bumper stickers that said, "Pray For Us We Drive Route 7" its more true today. On our stretch its always the screech of skidding tires, followed by the loud bang! Law enforcement patrol cars, ambulances, fire department vehicles responding to situations or events are so much more numerous now, when I was a kid it was not very often, now its like the nearby city !


You know that in VT seven is called the Molly Stark Trail. I was headed to MacFaddens once and as I came over the top in VT where it is real steep, there were seven bales of nice second cut hay that had fallen off a truck or trailer. I picked up five, then at Macfaddens I sold two for $7.50 each to a guy that needed something in the back for dunnage with a motor that he had bought.
The stretch profiled in the article is a scenic area, but all "S" turns, in the mid 80's they did re-align it better, at a high cost, but there just is no way to deal with it, its a pass between small mountains, before it was worse, and truck traffic was significant then, I cannot recall any of these kinds of accidents for years and years, now they are common and there is no doubt in my mind that its careless drivers.

Years ago, trucks were slow, drivers were more attentive or so it seems, and personally, as I did drive tractor trailers, I was always very careful, more so with a load on. These guys leaning these rigs over in turns, stressing the tires, pushing the limits today, makes no sense to me.

So yes, there is something to this, or so I believe.
Rt 7 accident
 
I spent many, many hours the last 15 years driving back and forth to DFW on I-35.

Definately more trucks from the border area running north and south. Mostly at night and they do run in drafting convoys. The run noticeably faster at night when there are less cars on the road; probably 80% or better truck traffic.

Mostly they are well behaved and reasonable. There seems to be about 10 loonies in four wheelers for every loony in a truck.

Most of the near-hits were in the local, small town area. Most of the heavy metroplex traffic moved without problem but you had to go with the flow. On 183 and 121 there were 55mph construction zones with all three lanes flowing at 70 day in and out! Anyone slowing down will cause a wreck. The cops don't pull anyone over because a: There is no physical place _to_ pullover and b: No room for a cop car to pull into the stream to get anyone.
 
For every truck that can run 70+, I can show you a company that limits their drivers to way less. One local private carrier is limiting their speed to 61 MPH by GPS. Anything over, the driver is docked pay.(how would you like to drive 500 miles a day on a 70 mph speed limit, and only run 61 mph?) We will be there in two more years(my company).
 
For a while here they were really slowing down. Probably when diesel got so high trucking companies tried everything they could to try to save on fuel. Now I see some (not all) picking up the pace again. Cheaper fuel and the aerodynamic kits might have something to do with it.
Some of these things really go and most are good drivers and just run with traffic whatever that happens to be that day. I have often wondered how much power some are making.
Back many years ago when Monfort was running a large packing plant in Greeley CO the cattle haulers used to flat get it on. The left lane was referred to as the Monfort lane. If you were in it you better be ready to drive because those boys pushed it hard all day. I remember some of those trucks would pour black smoke so bad if you were following you have to back off and let them get ahead a ways in order to see. One thing I notice now is you don't see near the black smoke any more even when they are really working them.

Greg
 
75 MPH is one thing. 120 MPH is a MUCH different thing.

Aerodynamic drag is a cubic function. I doubt if 1000 HP would pull an 80,000 box through the air at 120 MPH on level ground.

It's simple physics.

Dean
 
Around here it seems to be the BTO grain haulers in the fall. Pass everything on the road.
 
The Iowa80 truck stop museum has a truck that held the land speed record for a while. Was a pete, but stripped, lowered, and almost unrecognizable because it had so much aerodynamics attached. Even the cab was chopped. Had a v-12 dual turbo'd detroit that put out 1300hp and got a speed of 150 mph in the salt flats.
 
That, I can believe, Jon, but 120 MPH pulling a box, even unloaded, would take much much more than 500 HP.

Dean
 
That hill takes the ponies, but even worse is the hill into Mansfield starting under I-71 heading west. There you can get hung in the left lane due to merging traffic off of I-71. A full bucket of grain can easily drop you below 40 mph.
 
Dean, You are really a Doubting Thomas...Today!
It AIN'T Hard to build a truck that will run Over 100 MPH with an 80K load all day long
My cousin "Has" an old 96 convention Pete, Large Car, 250 wb+, 525 Cat 5+4, Progressive (No Wasted, useless gear slots) on 3:55 gears, this Sow will scare 95% of the Drivers out there! (other words the driver will chicken before it run out of throttle! He runs regularly @ 120 mph +! With a Weevil Wagon in the High Plains.
A Cummins KTA-600 with a 13 or 18 speed on 3:90s will get you the same thing!
With the new Dsl Technology there are a lot of really good engine, tranny, rear gears combos that will produce exactly what I say
*
NOW I will speak my mind, Most of my experiences come from 80s Technology! and we did it every Day. Real world experiences , and many many miles behind the wheel! it is evident You have No clue on how to say Truck much less drive, Shift or operate one, How to get your self out of a S#it Storm when the S#it start fall around you! You are a Nay Sayer, and Doubting Thomas, Ypou are a Nonbeliever, And it is best for you to simply Shut up.
H#LL 80K is a Cake Walk, Go to hauling 90K to 95K on loads there is where the Nut Cutting happens, Separate the Men from the boys! the Drivers form the Waneta-be, Hell we were All over loaded just who got caught!
Just because the Hands in your part of the world you know Don"t! Doesn't mean it hasn't been done before!
Later,
John A.
 
My road tractor was built in 1993 and at that time there was a big shift on to using larger engines in over the road trucks and running them slower for greater economy. (400 to 465 horsepower.) Most all these trucks came out of the factory with the computer set so they would govern out at about sixty eight to seventy miles per hour when in the highest gear. In a normal setting a inline six cylinder engine would turn up to 2300 to 2500 RPM's in all gears and when finally shifted to high the governor would kick in at about 1600 rpm's. This is one reason you will see a lot of trucks running at about the same speed. That being said all it takes is for the owner to have the dealership hook up their computer and either reset the governor setting or release it all together. Release it altogether and you can have a truck that will easily go up over one hundred miles per hour. The bigger engines really did help the fuel mileage and also you seldom needed to down shift on many of the grades.
 
Sorry, but I will not believe pulling an 80,000 box (even an empty box) at 120 MPH without seeing the speed slips.

It's simple physics.

Dean
 

Believe it, BTDT and NOBODY ever has the "Biggest Truck"..there is always one LARGER..
Crossing East from Elpaso at 90, I had a truck pass mine like I was backing up..and I was running a 3408 425 Cat, 13 over and 4.11 rear gears, he just ran away...claimed it would hit 137..!!

Speed is seldom the problem, it is HOW you are DRIVING.
A Driver can be a safety hazard at 45 mph, while the next driver is using GOOD judgement at a much higher speed..
The Worst driver to come across is one with 5 to 6 years "experience"...he thinks he KNOWS everything, is tired, run down and maybe taking some meds to stay awake and WILL run over you if you get in his way more than twice...
Those Rookies are what you must be cautious of..

Ron.
 
Several things here.

Some time ago at least Texas removed the 55 mph penalty for trucks and allowed them to go with the flow. This had plus and minus results but basically keeping traffic moving at the same pace worked best.

Next the railroad traffic that used to exist is now mostly over the road. The TX highway dept mentions that all the time in how hard a time they are having keeping the roads up with the increased truck traffic which really does a number on the pavement.

Next, recently TX. started raising speed limits on a lot of roads and apparently this helps to reduce congestion and is apparently working.

Remembering the short time I had a rock bucket, 400 big cam Cummins, power band about 300 rpm, 15 sp. we were limited to 55. As others have said that is a heck of a penalty on climbing a hill. Whenever we could we'd grab another 10 approaching the base of the hill and it really helped. Never saw a rig pulled over for doing that.

Last, you can't eliminate the idiot. Going to have them.



Mark
 
That was my point, if 1300 hp only gets 150mph with that truck it would take the same hp to pull a regular truck at 120 mph.
 
Must be nice to be able to sit there and count trucks going by day after day, year after year, to back your assertion that there is a "significant increase" in truck traffic.

Oh wait, you drove down the interstate ONCE, saw a bunch of trucks, and concluded that there was a "significant increase" in truck traffic...

It's holiday shopping season and fiscal year-end for many businesses, both of which cause increased truck traffic this time of year. Businesses are making last-minute capital purchases for tax purposes. Everyone else is buying Christmas presents. So, lots of extra trucks this time of year above and beyond normal.
 
(quoted from post at 19:27:38 12/17/14) 75 MPH is one thing. 120 MPH is a MUCH different thing.

Aerodynamic drag is a cubic function. I doubt if 1000 HP would pull an 80,000 box through the air at 120 MPH on level ground.

It's simple physics.

Dean

Thank you Dean!(twice!)
 
It's real. Dallas is on the corridor going North and East from the
south and vice versa for south bound traffic. It's a fact.

Mark
 
Not seeing the same thing. I'm not having any problems finding parking spots at night. I do think trucking is up, probably due to the holiday season, but no where near boom levels years ago. Back then you would wait hours upon hours to get loaded and unloaded. Finding a place to park was hard, a lot of times I had to shut down midday to find a parking spot.

I run 1350-1400 rpm @ about 63mph most all the time. Running under 65mph gets me about 7mpg's vs 4-5 running fast. I see very few trucks passing me.

Exceptions would be the log haulers in east TX, bull haulers in the midwest and the gravel trucks around Houston. They're the crazies as far as I'm concerned.

I can run 75-80 mph grossing 80K with ease. I'm running a 550hp Caterpillar C-15 engine in a Peterbilt w 13 speed trans.

This truck will run 100 but starts to heat up. I've never had the nerve to push it faster that that, It did have some hp&rpm's left so I believe 120mph is possible. This was across the west TX desert with no traffic. Not a regular thing with me.
a176975.jpg
 
Came thru Bowling Green, KY Tuesday night at 2AM.
Nbound Rest area on I-65 was full of semi's and both ramps were full both sides. Same on the opposite side rest area.

Maybe I am wrong but I drive a lot of miles on the interstate and they sure seem to be heavier with truck traffic. Lots of Auto plants around here and vehicle sales are up strongly....but, I am sure someone will argue sales are not up strongly,,,just moderately.
 
I've know doubt that in the bigger cities it's an issue. I run Houston to Minneapolis, mostly the Midwest. I also think it's a relative and regional thing. We're no where near levels of a few years ago.
 
(quoted from post at 09:54:14 12/19/14) Not seeing the same thing. I'm not having any problems finding parking spots at night. I do think trucking is up, probably due to the holiday season, but no where near boom levels years ago. Back then you would wait hours upon hours to get loaded and unloaded. Finding a place to park was hard, a lot of times I had to shut down midday to find a parking spot.

I run 1350-1400 rpm @ about 63mph most all the time. Running under 65mph gets me about 7mpg's vs 4-5 running fast. I see very few trucks passing me.

Exceptions would be the log haulers in east TX, bull haulers in the midwest and the gravel trucks around Houston. They're the crazies as far as I'm concerned.

I can run 75-80 mph grossing 80K with ease. I'm running a 550hp Caterpillar C-15 engine in a Peterbilt w 13 speed trans.

This truck will run 100 but starts to heat up. I've never had the nerve to push it faster that that, It did have some hp&rpm's left so I believe 120mph is possible. This was across the west TX desert with no traffic. Not a regular thing with me.
a176975.jpg

I read somewhere recently that at any given time 2% of the trucks that are supposed to be on the road are parked due to a lack of drivers.
 
I can only watch and wish. Not that I want to exceed the speed limit, but the company I drive for governed the trucks to 60 mph. In the truck I drive its 57 on the peddle, then bump the cruise a couple times and hit the wall at 59.6. In Oregon, the truck speed limit is 55. In Washington its 60. What frosts me is the idiots who merge into the freeway at 45-50 so you have to move over to make room, then pace you at your max warp speed so you have to slow to get back into the right lane.
Tim in OR
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top