Practical differences for having a flat or a nose front on a truck or a bus

Remember when the entire front end was covered in license plates from all over? Come to think of it, the License Plate Game must kind of suck nowadays.

I loved those. And rows of tax stickers on the doors. Now with apportioned plates, you only need one. Good for the truckers, bad for truck watchers.:slight_smile:

In the picture I linked of the Freightliner grain truck, you can see the little hinged piece of metal with the license plate. It’s bigger than. one plate because many were bolted to it, and up the front of the truck.

Note: I had to delete all the truck photos I had quoted in order to make this post (got a message that said I could not embed media) If a mod could put them back that would be great – they are in the thread already and which go where should be obvious. Thank you in advance.

These trailer connections are adjustable in two ways, first the turntable itself can be moved front to back but not a huge range. Also the trailer aka “box” or “flatbed” (no box covering the floor of the trailer) has a big thick necked ball hanging down that is on slides that can move up to seven feet (if memory serves, maybe more). That ball slips into the turntable which is somewhere over the two axles; when everything at that end is adjusted forward the cantilever puts whatever load is in the nose of the trailer onto the steers and more of the weight of the trailer onto the drives. The two pictured above are adjusted as far back as possible; if you shift them forward seven to nine feet they would look very different. Not sure what they are hauling (seems to be a reefer on the blue trailer) but it might not weigh enough for the weigh disbursement to matter at all.

As you can see in the picture, all of the trailer weight is directly on the drive wheels. If in your mind you shift the trailer forward so the place right behind the two axles is shifted to right in front of the two axles (and they CAN do that- every trailer can do it) you will see more of the load will be on the tractor frame which will add weight to the steers also.

Quick lesson on long haul truck wheels- there are three kinds:
~Steers do all the turning or steering and mostly hold the weight of the tractor motor plus a very little load. There are only two steer wheels (often they are taller than the drives or trailer wheels).
~Drives do all the driving, they are the only ones that move the rig frontward or backward. There are eight of them and they can carry about twenty thousand pounds total. They do not adjust (because they are connected to drive shafts) but where the trailer attaches to them can be shifted several feet as mentioned above.
~ Trailer tires can also adjust several feet, they are also attached to a sliding rail system with holes about every three inches. (Moving the axles forward puts more weight on them and less on the drives – moving them rearward puts more weight on the drives.) To adjust them front or back the driver sets the rear brakes, pushes the pins out of the way so they can slide then drives the rig frontward or backward to the desired location then puts the pins back in place, releases the brakes and goes through the scale again to see if he is legal. Trailers are usually two duelly axles close together but I have seen single tire axles with one super wide tire on it, and split axles with duel tired axles about twelve feet to twenty feet apart are becoming popular. I believe on traditional trailer axles you can put up to twenty-five thousand pounds but drivers prefer to have less ass end weight if possible. Split axles can carry up to thirty-six thousand pounds on each axle I am told but have never been able to understand why their weight capacity is so much larger.

If you followed all that, you know traditional rear axles (but not splits which can carry an entire legal load without any weight upon drives or steers) can be adjusted to shift weight to the drives or the drags (another word for trailer axles because they are dragged along behind the drives). In addition the attachment point of the trailer can be shifted to put more weight to the steers or the drives and also affects the drag axles. (The trailer connection point is not often adjusted unless it is a very odd load. If you are hauling twelve pallets of Styrofoam coolers in the nose and twelve pallets of lead or copper behind them that trailer will attach to the tractor as far forward as possible and the drags will be as far back as possible. That will shift as much weight as possible forward where the freight is very light. If it is all going to the same destination you would alternate the heavy and light materials when you load the trailer and not adjust anything.)

Most long haul trucks with sleepers weigh about 36 - 39 thousand pounds full of fuel and empty of freight. The max weight allowed in every state is eighty thousand pounds so a full load of freight is about 40-42 thousand pounds. Where I worked in Texas a truck can carry up to 85,000 pounds so sometimes we could send a truck out of Houston with 80,000 for new Jersey and four-thousand for say, Dallas but most drivers don’t want to drive only a few hours then stop and wait to be unloaded – especially if it is for just one pallet.

Where I was a dispatcher, rigs were weighed as they came in as well as on their way out and we often had to tell a driver to go fuel up before we loaded them because if we sent them out barely legal and they added several hundred pounds of fuel, well problems ensued.

This CF rig is being used for interstate it seems but it was designed for a local route I believe. Cab overs like this do not have sleepers and they do not have double axle drives either. I have only seen them used in two contexts. First as a yard vehicle moving trailers from location to location or plant to plant (like from a manufacturing plant to a warehouse plant) or more often as a LTL (less than load consolidator) who picks up small loads of freight from various businesses and brings them to a hub where they are shifted and sorted onto genuine long haul trucks to other regional hubs. In that role they almost always have a single pup trailer (the pic has two) and they cover the same ground every day and the driver sleeps in his own bed each night. I hear in places like Idaho and other Rocky Mountain states they use pup trailers (some states allow up to three!) because they turn better and handle the secondary highways better than 52 foot boxes which prefer interstates.

I have seen few cab-overs with sleepers in the last few years and I believe any trucker who does not have a sleeper sleeps at his own home almost every night. (It might be worth the company paying for a hotel every now and then - - surely not very often though.)

And finally to buses. Buses with flat fronts are very seldom cab-over rigs, they are usually diesel pushers (pusher = engine in the rear). That is what all tour buses and most city buses are and all high end RV’s are built on a bus chassis and are also diesel pushers. If a bus has a hood in the front it most likely runs on gasoline not diesel. My hometown has a free shuttle service that used be very small buses (almost vans and I think they had small diesels up front sort of half under/ half in front of the vehicle. Now they are all larger (but still not full size) buses and they are all diesel pushers. Our neighboring town has buses disguised as trolleys and they are certainly diesel (as their fumes advertise!) but I have no idea where they hid the motor on those things.

This cab-over DOES have a sleeper! How far does this farmer have to haul his grain? Don’t they have silos or railroads there?

I would guess you are right about the school buses, they were bought in small lots of two or five at a time, maybe even one at a time if the city had a sudden growth spurt and added a new route. The many different styles and presumably different manufactures might just indicate who had been elected to the school board the year each purchase was made. Mostly I believe you would want to stay with the company you are already buying parts from and you have a past with. Perhaps the past they have is bad so they went to the competition who was even worse then back to the original. Also some companies may have really good short buses but not so good full sized buses and a competitor vis versa.

As for city buses, they are always diesel pushers everywhere. Period. They run sixteen hours a day for many different drivers and must endure. School buses run, for the most part two short runs a day (under five miles in an urban area) five days a week usually with the same driver day after day. Sure some days there are field trips, and sometimes the team plays against a distant rival but they don’t grind like a city bus does. An easier to maintain gasoline engine will do the trick and the district probably has their own pumps which also gas up the “for official use only” district sedans also – so no need to buy and store diesel. Those are my best guesses- I really don’t know as much about buses.

In the UK, many but by no means all tractor units have adjustable fifth wheels. It’s not an expensive option and may avoid a hefty fine for overloading an axle.

We talk about axles here rather than wheels (18 wheeler makes no sense) and all articulated lorries have six axles. The trailer tyres are always ‘super’ singles but drive wheels are usually pairs.

Lift axles are common, both on the tractor unit and the trailer. Lifting a trailer axle is purely done to save wear when light, but either of the two axles on a tractor unit may be lifted either to save wear or to give extra traction on the drive axle.

On some tractor units, both rear axles are driven (2x4) but more commonly it is only one (4x2).

Lorries are limited to an overall maximum weight of 44 tonnes (97,000lbs) and 16.5 m (54 ft 2 in) in length. and 44 tonnes and 18.75 m (61 ft 6 in) for drawbar lorries. Most trailers can carry 26 standard UK 1200 x 1000 (48" x 36") pallets or 33 Euro 1,200 mm × 800 mm (47.2 in × 31.5 in) pallets. This is true for plain and insulated box trailers as well as curtainsiders.

Seconding and confirming what others have said. We don’t have dedicated school buses like in the States. They’re normal city/metro type coaches that have been pressed into school service.

Well, in the US, local public-transit buses also don’t usually have seat belts (though I think that inter-city buses like Greyhound and their competitors usually do). In fact, the riders of such buses often aren’t even seated.

In US cities the city buses are routinely used for schools too, sometimes with some special school routes and sometimes not. This generally only applies to the central city though. In suburbs and more rural areas there generally aren’t any city buses at all. Even where there are some suburban bus services, there’s no way they could handle all the school kids.

In the UK most kids make their own way or get driven to school. Where transport is provided it will be from a local contractor and may be a coach, minibus, or a taxi.

Service buses are not normally used although many kids will catch a bus or a train to school.

Great post. I’ll pick a nit and point out that the Chicago Transit Authority (and probably others) does have some hybrids as well some straight electrics.

I think trucks like this are former long-haul trucks. When the company or owner-operator trades them in, the dealer repurposes them on the cheap. On a used conventional, the sleeper can be removed and a plug panel can be easily put in the back of the cab to close it out*, but COEs would require major surgery. Though sometimes, people just like to spend money needlessly. :slight_smile: This truck was for sale and it had 800K miles on the clock.

So in a way, the stories your parents told you are true: the old “dog” got to go live on a farm.

*out here in AZ, we have a lot of trucks pulling dump trailers around. Someone is always moving dirt. So the market supports lots of small jobbers, and they start out with used trucks. It is funny seeing a dirt dump trailer being pulled by a long wheelbase Peterbilt with a double sleeper.

My brother drives short hauls and is home every evening. He and his co-workers convinced the powers that be to have trucks that have a small sleeper. For them, it’s mostly a place to keep their stuff. Perhaps some of them nap during lunch time or whatever.

Yes I would almost say that is the rule rather than the exception, but belly dumps like this are easy. An end dump that must raise and drive forward at the same time seem to be likely to tip over about half the time – the nose end up in the air seems to sway about twenty feet. The thing is if your company does any demo work you need end dumps because scrap will not come out of a belly dump correctly. But that is what all the materials handlers use because they are great for base gravel or sand or soil or any material like that. Asphalt requires end dumps too because they have to dump into those hoppers at the front end of those machines that lay and compact the material into road surface as they slowly creep forward.

I haven’t seen any lately (but there has been little work done over the last year, and I am sure not out viewing it when it does happen), but do you remember the end dumps with a trailer? The driver had to park the trailer and go dump the first bed attached to the chassis - - then back up to the trailer which was taller but narrower and it would be pulled into the original bed and then it was dumped. The oddest rig I have seen around central Arizona are those cotton haulers where the trailer is roughly a center poll attaching the rear axles and a giant bail of cotton pretty much duplicates the shape of a box trailer with metal uprights at each corner. The cotton pretty much IS the trailer.

mea culpa, I was working from memory and those just were not part of the landscape during the time in my mind. In fact, I believe we have some here also. Something else I forgot existed when I made that post was the very long city buses with the articulation in the middle but they are much in demand here with social distancing (until very recently).

Everyone in the US who works around freight thinks in terms of axles also, but tires are rated to carry certain loads (plus all the best truck driving songs mention how many wheels - not how many axles) so non truckers think in terms of wheels. Also, this is America so bigger is always better and eighteen wheels beats the hell out of five axles every day of the week and sounds way cooler!

One place where wheels rather than axles is important is when hauling very heavy earth moving equipment or excavators. They are far too heavy (and far too wide) for any conventional trailer. They have specialty trailers with three or four rows of tires (not actually axles- each hub is bolted directly to the trailer and there are usually eight across (I want to say I have seen ten across a very wide load trailer but my memory will not commit to that number). If there are three or four rows of eight tires in back – and then three or four rows of eight tires at the front end of the trailer (with a long arm that attaches to the tractor) that is a whole bunch of tires and you can divide the weight of the load by that many tires rather than across a few axles.

As for lifting axles, I see them mostly on specialty trucks with a chassis and only rarely on a tractor trailer rig. Many cement delivery trucks and sand/gravel delivery trucks (all on a truck chassis) have a third axle that can carry load when full- but are raised when returning to the yard empty. In a similar manner, Garbage trucks here often have a second rear axle that can be lowered to bear weight once enough has been collected to justify its use and it remains load bearing during the drive to the transfer station or dump and then raised to save wear on the tires while driving back to neighborhoods where the trash is collected empty. That makes sense because in each of those cases the vehicle is deadheading with no load (except its own empty weight) at least half of the time. Freight haulers hardly ever go very far without getting paid to haul something, so they generally don’t bother.

Wait, of all the millions of cab over trucks they pick the one with strippers on the side as an example!?

It is not a good picture, but the bus that serves my small city (pop ~5000*) has a nose front


  • (it transports to the much larger city across the river)

That’s a difference. In vic.aus I have never seen a “belly dump” trailer. I clicked on the link because I wasn’t sure what it would look like, and now I’m sure. Articulated dumpers and dump trailers are rare here, and never “belly dump” – I can understand the attraction, but what I see day in day out are short dumpers.
I’m guessing, looking at that picture, that it’s not a standard chassis? An end-dump, even a slightly long one, can be build on a standard chassis.

I think your talking about a Tandem-Pup. Dump the trailer, pull out and basically jackknife the trailer while you back main truck into the pile, dump, then pull out.

Best gig ever, and a very understanding boss. One of these days that boss may ask for an occasional overnight since he spent the dough for a sleeper.

What are the chances?!?

It is not a chassis at all – it is a trailer* That was the original point of the photo- that it is being pulled by a tractor designed for long haul freight rather than local materials delivery. The extra weight of that sleeper counts toward total weight so a very light weight tractor with smaller fuel tanks will allow for more payload. (If that tractor pictured weighed 32,000 pounds and if you assume the trailer empty weighs 10,000 pounds you can only haul 38,000 pounds. If you replace that with tractor weighing 22,000 pounds and the dead weight of the trailer stays the same, you can haul an extra ten thousand pounds on each delivery. (I pulled figures out of thin air – it would likely be less than ten-thousand pound but however much it is can be shifted to payload. You could also take the snow chains off the tractor too if you are less than an hour from home [and here you will never need snow chains.)

A couple of decades ago, very short dump trucks (2- 1/2 ton) with pretty high sides pulling a 25 or 30 foot flatbed trailer with a Ford or Case small earth moving tractor was standard and used by many trades. The tractor usually had a backhoe behind and bucket up front but sometimes it had a grading blade on the back. Plumbers and HVAC (and some off-site) used the backhoe; street repair, clean-up crews, and the grading services performed by surveyors for developers would used the blade. (Here almost all lots appear perfectly flat and level front to back and side to side; actually they all slope ever so gently [about 8" per fifty feet] in whatever direction the plot plan indicates - usually back to front to channel rainfall toward the gutters.)

If you were digging a trench for plumbing soil pipes or similar you left the excavated dirt there to be replaced and compacted once the inspectors okayed the install. For anything else you put whatever you excavated into the truck and hauled it away.

Long end dumps are for very heavy duty large scale jobs like paving a whole new subdivision of hundreds of homes or repaving a highway. They require quite a bit of infrastructure because the chassis frame must be over built to handle the enormous ram needed to lift the heavy ass drum. Even empty that thing weighs quite a bit and then you could have forty-five thousand pounds of material in it. You are only lifting one end of that but it still requires very powerful hydraulics. Many smaller companies don’t have enough work to justify a big ass end dump, but even fewer have use for a belly dump. Belly dumps are for large scale base material delivery companies only as far as I know. It is a very specialty use rig for sure.

I guess I wasted a whole lot of verbiage to say that a four ton dump truck will do most jobs fine but it will require many trips.

*unless by chassis you meant the structure of the trailer.

I am sure we are talking about the same thing they were certainly a tandem pup set-up, but the trailer does not have the ability to dump on its own. You must park the trailer first and dump the load on the truck chassis first. The yoke for the trailer hinges down and out of the way so you can back right up to the trailer. there is a heavy cable in a slot down the center of the truck bed; you latch that onto the trailer then pull some sheer pins to free the trailer bed from the axles. Then you reel in the cable which originates in the very nose of the bed and it pulls the narrower but taller sided container into the bed of the truck. Dump again just as you did the original load. I honestly do not recall if there was a mechanism to put the second container back on the axles or if they just pulled the trailer back as lonesome axles. In either case there had to be brake lights back there one way or another.

Wow. Yeah the tandem pups I’m talking about have the hydraulics on the trailer to dump on their own. I’ve never seen such a set up that you are talking about.

I had never seen the kind you are describing at that scale before. We have lift bed trailers here, but I can pull most of them behind my half ton SUV. (We learned accidentally to only operate them when they are attached to a vehicle when I was trying to slide some supplies off into my garage and the load became very rear end heavy and the hitch shot up off the ground and the half raised nose of the box punched a crease into my ceiling. Ooops!)

Here are a few videos of what I was talking about (although I have not found the exact ones I used to see here).

Here is one showing the whole operation including dump and putting the secondary box back on the trailer wheels. (He neglects to release the rear gate before the dump)

And here is a closeup of the details of loading/unloading the box and reattaching the lights and brakes. Notice about 2:20 when he comes back you know he released the gate because the hydraulics have moved freeing the bottom of the gate. Also the trailer hitch is covered in the sand that must have been in the box.

Thanks for the lesson on the pup trailer. In that case you need a whole separate ram to lift the trailer box, but in this transfer system you need all the transfer equipment which might be more complicated and expensive than a second ram (and heavier trailer frame).