question about american full rigs..

[haakon]

hi,just a question..why are all american trucks(full rigs) equiped with inline six engines? over here in europe many trucks like my scania has 16litre v8 with 620hp and almoust 4000 nm.. im just curius..:smile5:

 

[BigBlueChevy]

If you compare the Cummins turbo diesel(inline 6) to engines like the Duramax and Powerstroke(V8), anybody will tell you that the inline engines produce more low end torque(exactly what those rigs NEED).

You also need to consider that the inline engines have less parts than there V8 counterparts. Which means less things to go wrong, and less expenses for an overhaul. All which are big money saving factors.

Inline engines, being that the cylinders all stand vertical, isn't effected by gravity wearing the sides of the cylinder walls like a "V" engine will. A "V" engine will wear on the "outer" side of the cylinder wall just by the simple effect of gravity pushing down on it. Think of it from an engineering standpoint if you will.

I personally think its easier to work on Inline Engines as well. Sure there longer, but they lack the width of the "V" engines, which means more room for the mechanic and operators to do daily/preventive maintenance.

Add all those things up and some that I'm sure I've missed and naturaly both drivers and the actual buyer of the Rig will favor an inline engine more than a "V".

Why exactly Europe uses a "V8" instead of an inline engine I'm afraid I can't answer. Maybe they know something we don't?:confused5:

 

[dangerousdave]

USA is generally flatter than Europe, they use the HP to get it up those mountains faster, IMO.
Ever see a topographical or relief map of the earth?

 

[whatnot]

What is the max GVW there?

 

[Odlaw]

hi,just a question..why are all american trucks(full rigs) equiped with inline six engines? over here in europe many trucks like my scania has 16litre v8 with 620hp and almoust 4000 nm.. im just curius..:smile5:

Not all american trucks have inline six's....in fact other than a couple of cummins friends I don't know a single person that has a inline six in their truck - all have v8's.

 

[WarWagon]

We don't "need" that kind of class 8 power here.

Mainly because the 6 cyl engines are put in trucks that are built cheaper. The bean counters cut off funding for the #7 and #8 cylinders leaving a chronic miss on these engines. They are also less complex and easier to work on. Nothing hidden the the "V".

However the distances you can travel make the bean counters right. Lighter engines mean more cargo. Less upfront cost. Perhaps better fuel economy on the flat lands. Most countries over there are smaller than some of our States. So slowing traffic down on the hills here is the accepted norm. These 6 cylinder handicapped semi trucks, and Dodge pickups, are the ones I am passing (sucking the doors off) with my V-8 Duramax pulling a 8% grade with a 48' bunkhouse trailer behind me. Yet, in the flats the 6 gets better MPG than I do.

You can get a lot of power out of a inline 6. Just ask the Dodge guys. So power output and reliability are not really a big factor. Because the power needed here doesn't affect reliability with 6 cylinders.

When you think of the weight of the piston assembly and compare it to the torque and HP output of the engine... The V configuration has zero wear from gravity. The 500+ Ft-LBS transferred via the rod and angle off the cylinder wall is a lot more stress/wear on the cylinder walls than the light weight aluminum piston could ever put on the walls due to gravity alone. (The ring pack puts an even high pressure all around the bore no matter the configuration.)

All the above said it is still cheap that is your answer. 6 vs. 8 injectors when you have to replace them. The miles trucks see here - yeah when you replace them from wear!

Move up to construction equipment and you get 8 and 16 cylinder engines for the power requirements.

 

[635]

I believe 'haakon' is talking about "Big" Rigs, Semis!

I my driving experiences, most of the rigs I drove had in line 6's. Mack had a couple of good V-8s. Early Detroit 2 stroke 318 V-8s and later 8V92's. A 3408 Cat was one early power house. One log truck I drove for a few years had a 12V71. The big engine companies found they could make the same power and even more power with the 6 with less engine weight. And that made room for more freight.

The highways here in the US are mostly flat in the midwest as dangerousdave said. The new in line 6's produce a lot of HP and torque. And they are in the range of 500 to 625hp.

Most of the legal highway weights here in the US are 80,000 with some being 105,000.

 

[BigBlueChevy]

When you think of the weight of the piston assembly and compare it to the torque and HP output of the engine... The V configuration has zero wear from gravity. The 500+ Ft-LBS transferred via the rod and angle off the cylinder wall is a lot more stress/wear on the cylinder walls than the light weight aluminum piston could ever put on the walls due to gravity alone. (The ring pack puts an even high pressure all around the bore no matter the configuration.)

Guess it must be one of those old wives tales. I don't hear it often, but every now and then I'd hear someone mention how having an inline is better... yada yada yada... "and the cylinders don't wear like they do on a V engine cause they go up and down so no wear damage from gravity"

So most of the trucks do come as V8's then? I would say 95% of all of the trucks I have seen around here all have inline engines. But since you mention the hills factor most of Jersey is pretty flat. At least, if your comparing it to out west and Pensillvania(sp?) So I guess in a way naturally Jersey trucks would be inline engines then...

Damn I need to get out of this state more.:rolleyes5:

 

[haakon]

What is the max GVW there?

Here in norway its 50 000kg or 110231pounds on six axle semi trucks or the more common truck and trailer,a tree axle truck witha tree axle trailer behind it..on timber trucks its 132000pounds and some dump trucks can go with 154000p..sorry my english.. its not wery common with tandem trucks here but an axle behind the drive axle whom you can lift,thats alot better in the winter when you go empty.. up the hills you lift the rear axle,giving more gravity and grip on the drive axle:smile5:
speaking of winter,we also have sand boxes with heaters in front of the drive axle,just push the button in the cab and warm dry sand comes out in front of the drive,helping you get up the hill:smile5:

 

[haakon]

I believe 'haakon' is talking about "Big" Rigs, Semis!

I my driving experiences, most of the rigs I drove had in line 6's. Mack had a couple of good V-8s. Early Detroit 2 stroke 318 V-8s and later 8V92's. A 3408 Cat was one early power house. One log truck I drove for a few years had a 12V71. The big engine companies found they could make the same power and even more power with the 6 with less engine weight. And that made room for more freight.

The highways here in the US are mostly flat in the midwest as dangerousdave said. The new in line 6's produce a lot of HP and torque. And they are in the range of 500 to 625hp.

Most of the legal highway weights here in the US are 80,000 with some being 105,000.

Here in norway there is almoust only hills,i understand the different need for engines if its flat..the cost of an overhaul isnt realy an issue here cause the companies change out the trucks when they have 500 000km on them,others drive them to almoust a million,but then the rest of the truck is worn out too so its more economic to buy a new one..besides no drivers here wants an old truck..and moust of the european trucks are plastic and shit so a million is the moust they can take..

 

[635]

Your English is better than my Norwegian!

Here in the US 80,000 is with 5 axles. 105,500 is with 8 axles in Washington and a few others. We use lift axles also but in front of the drive axles on freight trucks. Some dump trucks have a lift axle on the rear under the lift gate. The most I've seen here in Washington State is 4 lift axles, one steer axle, and 3 drive axles on one very long truck with no trailer. But then there are some with 2 steer axles, 2 lift axles, and 2 drive axles. Here a big truck can weigh 12,000 on the front axle and 34,000 on each tandem axle set. A 3 axles spread is good for 43,000 and 4 axles are good for 50,000. AND a spread axles is good for 40,000. A single axle is good for 20,000 so with a 10 foot spread the trailer can carry 40,000.

I haven't seen any sand boxes on big trucks, only school buses. Here we use good old tire chains, singles and 3 rails. I have thrown my share of them day after day. There used to be a company that made automatic chains. Flip a switch and they would drop a wheel against the tire and a bunch of loose chains would then spin under the tire for traction. Those drivers would usually wait until it was too late to flip the switch or the system, which was out in the very cold air, would freeze.

My trucking days are long over but I can still remember them very clearly!

 

[635]

Then there are states, mostly east of he Rocky Mountains, where it is legal to carry even more weight on the US (State) highways than you can carry on the Interstate Highway system. And a lot of truckers complained about filling out their log books!

 

[btfarm]

War Wagon is right about how a V configuration will wear the piston skirt from the reaction of the power cycle Jamie. You were misled a bit there...):h That still happens on an inline but not as pronounced.

Speaking of sanders, they were common on the western rigs back in the 50s to early 60s. Dad had one truck in the late 50s with them when he ran western routes. I believe it was an IH V8 referred to at the time as a "binder".

From the Colorado State tire chain regulations:

Approved Alternative Traction Devices (ATD's)

Approved ATD's may be used instead of chains. These include wheel sanders (vehicle must carry enough sand to negotiate the hill), or pneumatically driven chains which when engaged, spin under the drive wheels automatically as traction is lost.

 

[Anubis]

how fast you guys in europe need to go? I got a 565 cummins (ISX .... Inline 6) with an 18spd that will run tripple digits....... I still think it is the biggest POS motor cummins ever put out (mostly due to chronic Turbo and EGR problems)........ I pulled Cajon Pass at 47mph with 47,XXXlbs on my sled (approx 78,000lbs) with my Last tractor ..... that had a 14.0L Serries 60 Detroit set at 515hp and 1850lbs torque backed up with an 18spd.

how many miles (km) you getting out of those V8s ...... I had a tractor with a 12.7L inline 6 go 1.2 million miles with out an overhaul....... would still be going if I hadn't wrecked it.......

 

[635]

47mph up Cajon Pass is really doing a good job!

 

[DEERE3594]

haakon, If you want to see some pictures of American big rigs, check out this thread if you havnt already:
http://www.thetruckstop.us/forum/showthread.php?p=235720#post235720

 

[CUCV]

635- those instant-on chains were made by a company called On-Spot. We had them on our Navistar 4700 medium duty rigs. They worked but after 1 or 2 engagements the chain would break, requiring a new wheel as all the chains were welded on. A competitor came out with bolt-on links but their name escapes me. They saved my butt on ice once or twice, and not having to put on chains was always welcomed!

 

[ak diesel driver]

All the school buses around here use those style chains

 

[Anubis]

47mph up Cajon Pass is really doing a good job!

not that hard if the scale is closed and nobody sees you get out in that left lane..... I remember when I first started driving I started with a 325hp M-11 ...... down to the bottom side of the straight 10 and 20mph @ 66,XXX lbs on Cajon......

I have only been driving for 12 years and trucks have come a long ways in power in 12 years.

I was talking to a dude with a 750hp 3406e at a truck show, he showed me a speeding ticket he got Northbound on the Grapevine (61 in a 55) loaded at 78,XXX lbs........... I wonder what his gearing was....

thread jack over.

 

[3500GMC]

The Scania big trucks are a cab over engine, right? Maybe designers like the packaging of the big V8 over the inline 6.. ? The Scania trucks appear to be pretty darn short too. Perhaps they have to work within overall tractor-trailer length permitted on the roads in Norway.

FYI a Caterpillar C-15 is a 15.2 liter inline 6 that has to comply with the more strict U.S. emission specs.

All this while still making up to 600 HP.

Inline sixes have 7 main bearings. V8's have 5.