I-shifts & other auto box attrocities

[juddian]

kitbuilder123:

Juddian:

kitbuilder123:
J/quote]

I agree on the electric pto control, air switch linked through the hand brake is definitely better but because it’s auto with no clutch pedal, it needs electrics to tell it to engage the clutch and when to release it again

Ah, i overlooked the auto clutch bit, but then i have an excuse, i still live in the utopian world called KISS, Keep It Soddin Simple.

The older i get and the more bloody complicated stuff gets the more i want a HINO, simple old school motor with a manual…thankyou Lord…gearbox.

[kr79]

Carryfast:

kr79:
The 13 speed fuller is more than adequate unless you are pulling super heavy weights. After my little jaunt across the pond the thing you see with the average American or Canadian truck driver is they seem to think they have to use every single gear. NMM will confirm it seems to take them half a dozen gearchanges to get across the lights burning more fuel than is needed making noise and going no where.

Like this you mean .

youtube.com/watch?v=j0n9_E0HBSY

It’s actually saving the guvnor money in fuel costs not burning it.

Well as its pitch black and we don’t know how big the truck is or what the road is like I’m talking on the flat pulling one empty or lightly loaded trailer.
These days we are taught to get the vehicle up to crusing speed as quick as possible.

[newmercman]

Your idea of progressive shifting and the practice in North america are two completely different things Carryfast

What we call progressive shifting is the normal and proper way to drive a lorry, you shift at the upper end of the torque curve (c.1500rpm) and that takes the revs back down to the start of the peak torque (c.1000rpms) nothing wrong with that at all

However, the backward imbeciles here do it differently, they pull away without the throttle and let the electronics supply the required amount of fuel to get moving, then they repeat this process all the way until top gear, using hardly any throttle at all. What this means in practice is they move off very slowly and use every gear they have, not getting far in the process

As long as you drive within the confines of the torque curve you will use no more fuel than is necessary, it’s pure and simple physics. To move a specific mass from rest to a specific speed with a specific amount of resistance requires the same amount of energy. Energy is provided in a lorry by one thing, diesel fuel. So unless you change any of the factors, like rolling or aerodynamic resistance, the weight of the load, or the gradient, you will use the same amount of fuel no matter where your foot is on the throttle, as long as you’re in the correct rpm range, so doing it as fast as you can with your boot on the carpet, or driving as if the throttle pedal is on fire will make absolutely no difference at all to fuel consumption

This is the part this lot over here do not understand, because they’re not on the throttle, they think they’re saving fuel, but that is wrong, the electronics will be supplying fuel based on the rpms and the engine load, so poodling along in too high a gear will use more fuel than using full throttle in the correct gear. But these are the same people who will leave their truck on high idle (1200rpms) for an hour to warm it up or cool it down at the start/end of a shift, they think a Harley is the ultimate in two wheeled travel FFS

They also think that nailing a 30’ mudflap to the side of a trailer will save fuel, when anyone with half a brain will tell you that anything that moves in the airstream (as these sideskirts do) is creating turbulence, which is the number one enemy of aerodynamics

[carryfast]

kr79:

Carryfast:

kr79:
The 13 speed fuller is more than adequate unless you are pulling super heavy weights. After my little jaunt across the pond the thing you see with the average American or Canadian truck driver is they seem to think they have to use every single gear. NMM will confirm it seems to take them half a dozen gearchanges to get across the lights burning more fuel than is needed making noise and going no where.

Like this you mean .

youtube.com/watch?v=j0n9_E0HBSY

It’s actually saving the guvnor money in fuel costs not burning it.

Well as its pitch black and we don’t know how big the truck is or what the road is like I’m talking on the flat pulling one empty or lightly loaded trailer.
These days we are taught to get the vehicle up to crusing speed as quick as possible.

It doesn’t really matter because all that was meant to show was the most efficient way to do as you say in getting the vehicle up to speed.

The most fuel efficient way of doing that is by using lots of short shifted gearchanges.Not by using less gears which is just the same thing as turning a close ratio multi speed transmission back into an inefficient wide ratio one which by definition means that the engine has to be run up to higher rpm before upshifting it and that makes no difference wether it’s loaded or not.The only difference is that the fuel consumption and engine wear rate will be even worse in the case of doing that with a fully freighted truck because of the combination of high load and higher engine speed than just upshifting it much sooner into a higher gear that’s close enough in ratio not to bog the engine down too low in the torque band.

It’s all about driving a diesel engine as it’s meant to be driven over as narrow a rev range as possible,as far below the power peak as possible while still maintaining good progress which means lots of short shifted upshifts using a close ratio box to keep road speed as high as possible while engine speed is kept as low as possible and if the customers thought that a 13 speed is always good enough for that then there wouldn’t have been any point in demanding an 18 speed.

youtube.com/watch?v=232B3Uakous

[carryfast]

newmercman:
Your idea of progressive shifting and the practice in North america are two completely different things Carryfast

What we call progressive shifting is the normal and proper way to drive a lorry, you shift at the upper end of the torque curve (c.1500rpm) and that takes the revs back down to the start of the peak torque (c.1000rpms) nothing wrong with that at all

However, the backward imbeciles here do it differently, they pull away without the throttle and let the electronics supply the required amount of fuel to get moving, then they repeat this process all the way until top gear, using hardly any throttle at all. What this means in practice is they move off very slowly and use every gear they have, not getting far in the process

As long as you drive within the confines of the torque curve you will use no more fuel than is necessary, it’s pure and simple physics. To move a specific mass from rest to a specific speed with a specific amount of resistance requires the same amount of energy. Energy is provided in a lorry by one thing, diesel fuel. So unless you change any of the factors, like rolling or aerodynamic resistance, the weight of the load, or the gradient, you will use the same amount of fuel no matter where your foot is on the throttle, as long as you’re in the correct rpm range, so doing it as fast as you can with your boot on the carpet, or driving as if the throttle pedal is on fire will make absolutely no difference at all to fuel consumption

This is the part this lot over here do not understand, because they’re not on the throttle, they think they’re saving fuel, but that is wrong, the electronics will be supplying fuel based on the rpms and the engine load, so poodling along in too high a gear will use more fuel than using full throttle in the correct gear. But these are the same people who will leave their truck on high idle (1200rpms) for an hour to warm it up or cool it down at the start/end of a shift, they think a Harley is the ultimate in two wheeled travel FFS

They also think that nailing a 30’ mudflap to the side of a trailer will save fuel, when anyone with half a brain will tell you that anything that moves in the airstream (as these sideskirts do) is creating turbulence, which is the number one enemy of aerodynamics

The only point I’m trying to make is that in general it’s a lot easier to keep the engine speed down and road speed up by having loads of close ratios rather than less and I think that’s the (correct) logic that Fuller is going by in putting the extra 5 speeds into the box.But what the drivers actually do with them when they’ve got them seems to be another matter.

[dafmad]

I have driven most of the Autos and by far the worst is the MAN Tipmatic, ■■■■■■■■ rubbish.
Btw its nothing to do with who made the hardware, ZF or whoever its the programming, which must have been done by a retired granny cyclist Because thats how its drives. You daren’t let go of the throttle, cos if you do you have to wait seemingly several seconds before you get full throttle back, whether its changing gear or not
The Geartronic was better lol

[newmercman]

Carryfast the Fuller 18spd is a basic four over four with a splitter, so in normal use, it’s a 16spd box. The other two speeds are crawler low and high split, in fact it’s a 20spd box really as you can use low and high split crawler in high range too

They are a bit over the top for normal on highway use, a 13spd will get you anywhere an 18spd will, as you rarely need the splitter in low range, but when you’re pulling 62tons over the Rockies, I’m sure that every single gear can be useful. However, I don’t pull 62tons, just a paltry 36tons most of the time, so the 18spd is overkill really in my job

In fact, driven properly, a 9spd with no splitter at all would do the job just as well, the big CAT has a nice flat torque curve spread over 500rpm, so the extra gears are unnecessary if you know what you’re doing and if you don’t know what you’re doing, you could waste a lot of time and fuel poncing about making gear changes when you don’t need to

Which is the main reason why the big fleets spec simple gearboxes (or autoshifts) that way they minimise the impact the driver can have on their bottom line. Fuller even manufactures a convertible transmission, it comes out of the factory as a 9spd, yet with a few twirls of the spanners, it becomes a 13spd, very popular with the fleets, they get a nice simple 9spd for their steering wheel attendants and a 13spd for when they sell it

[greek]

Dont know whos winding who here nmn, about time you give us another diary from your end so us old ■■■■■ can see what we`ve missed, instead of wasting time with cf, because no matter what you write he will just keep coming back

just as an add on getting new Merc auto this week, which suits me as the new ones work well although wished they had left the gearstick on the armrest just in case I want to drive in manual

[kr79]

Thanks Mark for explaining what I was trying to explain to the king of the gear hammers in much more detailed terms. No doubt it will be wrong because some you tube video says different.

[tony_taylor]

A lot of opinion seems to feel that autoboxes are a relatively new innovation when the fact is they have been around for many years.Not in the same numbers I grant you but nonetheless they have been here in one form or another for ages.The army have had them for donkeys years,Leyland Atlantean buses had them, albeit as a pre select fluid flywheel model.American cars(ok cars) have had them since the fifties.The general concensus seems to be that they are fine for city work but are not really needed for long haul work.While that may be fine for the US,Canada and Australia,I don’t think that’s the case in western Europe,you cannot go very far without meeting congestion of some sort or another.The distances between cities are getting shorter and the case for autos is becoming stronger,especially as some of the old school think that there are more SWA’s than drivers nowadays.The fact is (as has already been stated in previous posts) they save money in the long run.Despite the teething troubles they have now,they will only get more efficient as time goes by.So, I say accept them and adapt because they are here to stay.

[juddian]

Tony Taylor:
A lot of opinion seems to feel that autoboxes are a relatively new innovation when the fact is they have been around for many years.Not in the same numbers I grant you but nonetheless they have been here in one form or another for ages.The army have had them for donkeys years,Leyland Atlantean buses had them, albeit as a pre select fluid flywheel model.American cars(ok cars) have had them since the fifties.The general concensus seems to be that they are fine for city work but are not really needed for long haul work.While that may be fine for the US,Canada and Australia,I don’t think that’s the case in western Europe,you cannot go very far without meeting congestion of some sort or another.The distances between cities are getting shorter and the case for autos is becoming stronger,especially as some of the old school think that there are more SWA’s than drivers nowadays.The fact is (as has already been stated in previous posts) they save money in the long run.Despite the teething troubles they have now,they will only get more efficient as time goes by.So, I say accept them and adapt because they are here to stay.

Couple of points with your valid post Tony.

Lets not confuse the fact that the current misnamed auto boxes we have to put up with in modern trucks are not automatics in the true sense of the word, they are manual gearboxes with a computer, sensors and motors operating the clutch and selecting the often inappropriate gear and changing it.

They bear no relation to silky smooth infinitely variable torque converter hydraulic boxes, and i’d give me eye teeth for such a proper auto box, probably Alison, in a truck with a ■■■■■■■ or other proper engine.

I take the opposite view to you in that in congestion and short haul i’d sooner have a manual every time, no programming can infinitely adjust throttle gear and clutch like a real driver, its always a compromise via a set of given parameters…i always liken automated manaul gearbox driving like trying to drive the throttle and brake pedal only and getting your co driver to operate the clutch and change the gears whilst not communicating in any way, only going by feel.

When PSA group started putting the Sensodrive automated manual later to be renamed EGS or summat i was at the time driving transporters, getting these things (other makes every bit as bad but PSA was 90% of my work) to give the necessary fine control needed for loading was frustrating to the nth degree.
I had an interesting conversation with a sales manager at one dealership who informed me that whilst manoeuvering and stop start wasn’t their best environment, that they were excellent on the motorway… …would that be the motorway that you don’t change gear on? i politely enquired. .

The first automated manual lorry i drove was an ('93?) L plate FL10 with Geartronic, it proved good was just as fast as manuals in practice and was competent at manoeuvering given its limitations, its now called i Drive and despite the name change feels exactly the same as 20 years ago…the early ones had problems now and again, needed mainly electronic work several times on the one i drove regularly.
All Volvo automated manuals since then have felt just as good, apart from one hire unit that had serious programming issues and had other preculiar faults too, probably abused or shorted out at some point, and i’ve driven dozens of differing autos so feel reasonably qualified to select Volvo as being ahead of the field by a country mile, drove a new one couple of weeks ago for 2 days, still the benchmark, and still feels like Geartronic in that FL10.

My first non Volvo auto was a 3 pedal automated manual Scania in 2006, couldn’t have been further from the Volvo (replaced FM) in competence, and within 3 weeks, after the auto stalled the engine on me whilst straddling a major road after turning onto it from a steep hill i drove it from that moment on for the next 3 years in manual override, my truck ironically proved the most economical in the depot fleet (and i’m not a 50 mph cruiser), and the ability to start from rest at an adequate rate using the correct gears for the situation selected quickly, not wait interminably for the idiot box to shuffle the first 2 changes up as you flop like a dying fish onto a busy roundabout amid the horn blasts and strange hand signals.
Where the Scania scored was by keeping the clutch pedal, thereby leaving the driver to control stops, starts and manoeuvers, this worked out the best of both worlds for me.

Since then i’ve regularly driven the later 2 pedal Scanias, same box that needs to be driven manually, but now lacks the ease of manually controlled manoeuvering and start/stop control, a backwards step IMO.

As for fuel consumption, my findings are that (Volvo excepted, i found no need to override but others may have experimented) driven manually the vast majority of these automated manuals give better economy via lower revs, better utilisation of torque, and better unbaulked constant progress than the auto only programming can produce, the program cannot at this stage predict terrain and traffic, though terrain will be on the menu when GPS integration of the truck control is perfected (and therein lies the recruitment of licence holders of even less use, can’t wait… )the machine will never be able to beat a proper driver in my humble…mind you finding proper drivers is bad enough now mostly bloody old and knackered, by the time the machines take over completely the timing may be about right.

Agreed, they are here to stay, doesn’t bother me…no actually it does but sod all i can do about it unless i go OD…i enjoyed being a driver when the term meant something, my only destination now is going home to my lovely wife at the end of my shift, fortunately unless due to unforseen circs i don’t have to sleep in the bloody tin can, what i drive really counts for bugger all any more its just an electronic vehicle with a steering wheel (at the moment) whatever the make, not much difference between any of 'em at the end of the day.

PS…strewth my speeling goes to rats when in the flow, and sorry about the long winded post.

[v8lenny]

Carryfast:
It doesn’t really matter because all that was meant to show was the most efficient way to do as you say in getting the vehicle up to speed.

The most fuel efficient way of doing that is by using lots of short shifted gearchanges.Not by using less gears which is just the same thing as turning a close ratio multi speed transmission back into an inefficient wide ratio one which by definition means that the engine has to be run up to higher rpm before upshifting it and that makes no difference wether it’s loaded or not.The only difference is that the fuel consumption and engine wear rate will be even worse in the case of doing that with a fully freighted truck because of the combination of high load and higher engine speed than just upshifting it much sooner into a higher gear that’s close enough in ratio not to bog the engine down too low in the torque band.

It’s all about driving a diesel engine as it’s meant to be driven over as narrow a rev range as possible,as far below the power peak as possible while still maintaining good progress which means lots of short shifted upshifts using a close ratio box to keep road speed as high as possible while engine speed is kept as low as possible and if the customers thought that a 13 speed is always good enough for that then there wouldn’t have been any point in demanding an 18 speed.

youtube.com/watch?v=232B3Uakous

Who taught you that BS? Some stupid american?

Do you know what a turbocharger is and how that works? Turbo is the reason to skip as many gears as possible to save fuel. During every shift you lose boost and have to use energy to get it back again, that’s why you make as few shifts as possible to get up to speed.

[kr79]

He saw it on you tube must be true.

[carryfast]

V8Lenny:

Carryfast:
It doesn’t really matter because all that was meant to show was the most efficient way to do as you say in getting the vehicle up to speed.

The most fuel efficient way of doing that is by using lots of short shifted gearchanges.Not by using less gears which is just the same thing as turning a close ratio multi speed transmission back into an inefficient wide ratio one which by definition means that the engine has to be run up to higher rpm before upshifting it and that makes no difference wether it’s loaded or not.The only difference is that the fuel consumption and engine wear rate will be even worse in the case of doing that with a fully freighted truck because of the combination of high load and higher engine speed than just upshifting it much sooner into a higher gear that’s close enough in ratio not to bog the engine down too low in the torque band.

It’s all about driving a diesel engine as it’s meant to be driven over as narrow a rev range as possible,as far below the power peak as possible while still maintaining good progress which means lots of short shifted upshifts using a close ratio box to keep road speed as high as possible while engine speed is kept as low as possible and if the customers thought that a 13 speed is always good enough for that then there wouldn’t have been any point in demanding an 18 speed.

youtube.com/watch?v=232B3Uakous

Who taught you that BS? Some stupid american?

Do you know what a turbocharger is and how that works? Turbo is the reason to skip as many gears as possible to save fuel. During every shift you lose boost and have to use energy to get it back again, that’s why you make as few shifts as possible to get up to speed.

If you and nmm are right then transmission manufacturers like ZF and Eaton/Fuller have all been wrong over the years and boxes like the 16 speed ‘eco’ split etc would actually have been the best way to turn an economical wagon into a thirsty one and manufacturers like DAF etc etc would have only have used 9 speed transmissions at most because,in your view,making more gear shifts,using more gears,uses more fuel not saves it.

If it’s losing boost,by upshifting early into a higher (but close) gear ratio,then how do you think all that torque below 1,500 rpm in most cases is made. . It’s the issue of keeping the boost levels and roadspeed up at the same time as keeping engine speeds as low as possible that makes the case for multi speed close ratio transmissions.If I’m wrong then all the major truck transmission manufacturers have also been wrong over the years.The fact is just because an engine has a wide torque band doesn’t mean that it won’t be more economical to still drive it over as narrow a part of that as possible using only a fraction of what is actually available.Which is why no one,with any sense,would fit a 9 speed transmission in a V8 Scania for example.

But ‘stupid Americans’ who were using 13 speed transmissions in their trucks while most of the Brits were still using 6 speeds or 9 at best you mean.

[carryfast]

newmercman:
Carryfast the Fuller 18spd is a basic four over four with a splitter, so in normal use, it’s a 16spd box. The other two speeds are crawler low and high split, in fact it’s a 20spd box really as you can use low and high split crawler in high range too

They are a bit over the top for normal on highway use, a 13spd will get you anywhere an 18spd will, as you rarely need the splitter in low range, but when you’re pulling 62tons over the Rockies, I’m sure that every single gear can be useful. However, I don’t pull 62tons, just a paltry 36tons most of the time, so the 18spd is overkill really in my job

In fact, driven properly, a 9spd with no splitter at all would do the job just as well, the big CAT has a nice flat torque curve spread over 500rpm, so the extra gears are unnecessary if you know what you’re doing and if you don’t know what you’re doing, you could waste a lot of time and fuel poncing about making gear changes when you don’t need to

Which is the main reason why the big fleets spec simple gearboxes (or autoshifts) that way they minimise the impact the driver can have on their bottom line. Fuller even manufactures a convertible transmission, it comes out of the factory as a 9spd, yet with a few twirls of the spanners, it becomes a 13spd, very popular with the fleets, they get a nice simple 9spd for their steering wheel attendants and a 13spd for when they sell it

Everyone knows that the total gears available in a 12-18 speed box isn’t what’s actually used most of the time in the real world.But the fact is the more there are then the closer they’ll all be which is what matters.
So what you’re saying is more contradictory explanations which seem to go against not only accepted transsmision development in the States but also in Euro Land because 12-16 speed boxes were put into common use here too usually (correctly) on the basis that the higher the power (and therefore torque) output the thing had/has the more gears it needs to get the ratios close enough so as to exploit the extra torque while keeping the thing as far below the power peak as possible.

The idea of using less gears to suit the steering wheel attendants,because they don’t know why all those gears are there in a 13-18 speed box,is just costing fuel in just the same way that using auto boxes,because too many drivers aren’t up to the job,costs money at the end of the day that could have been saved if those drivers knew what they were doing.

[zb_anorak]

V8Lenny:

Carryfast:
The most fuel efficient way of doing that is by using lots of short shifted gearchanges.
It’s all about driving a diesel engine as it’s meant to be driven over as narrow a rev range as possible,as far below the power peak as possible…blah blah

Who taught you that BS? Some stupid american?

Do you know what a turbocharger is and how that works? Turbo is the reason to skip as many gears as possible to save fuel. During every shift you lose boost and have to use energy to get it back again, that’s why you make as few shifts as possible to get up to speed.

If you look at the SFC graph of any engine, it only gets about 10% worse, at full load, at the extremities of the speed range, than it is at the minimum point. Below full load, it gets significantly worse until, at idle, the efficiency is zero, as you would expect. In other words, the engine is actually much more efficient at full power than it is at half load, low revs. The other major factor is transients. During a change in load, the engine is far less efficient than it is in steady-state conditions, for the reason that V8lenny stated.

For these reasons, magazine roadtesters frequently mention that the manufacturer has told them to blast up to speed as quickly as possible, using full throttle, revs up to peak power and as few gearchanges as possible.

This is my explanation why V8lenny is 100% efficient, while cf is, as usual, blipping his throttle in the yard- wasting fuel and going nowhere.

[carryfast]

[zb]
anorak:

V8Lenny:

Carryfast:
The most fuel efficient way of doing that is by using lots of short shifted gearchanges.
It’s all about driving a diesel engine as it’s meant to be driven over as narrow a rev range as possible,as far below the power peak as possible…blah blah

Who taught you that BS? Some stupid american?

Do you know what a turbocharger is and how that works? Turbo is the reason to skip as many gears as possible to save fuel. During every shift you lose boost and have to use energy to get it back again, that’s why you make as few shifts as possible to get up to speed.

If you look at the SFC graph of any engine, it only gets about 10% worse, at full load, at the extremities of the speed range, than it is at the minimum point. Below full load, it gets significantly worse until, at idle, the efficiency is zero, as you would expect. In other words, the engine is actually much more efficient at full power than it is at half load, low revs. The other major factor is transients. During a change in load, the engine is far less efficient than it is in steady-state conditions, for the reason that V8lenny stated.

For these reasons, magazine roadtesters frequently mention that the manufacturer has told them to blast up to speed as quickly as possible, using full throttle, revs up to peak power and as few gearchanges as possible.

I bet that idea worked just great and did wonders for the fuel consumption of a V8 Scania or big cam ■■■■■■■■■■ might also explain some of the figures obtained from that other unmentionable thirsty American motor.

[tony_taylor]

Juddian,I agree with you,real driving is a dying art,but I don’t think that it’s all the fault of the young men and women entering the industry today.After all, most are never going to get the chance to aquire the skill and judgement it takes to use the gearboxes that we were brought up on.As for fuel consumption, that has always been in the hands(and feet) of the driver whether driving an autoshift or not.Me and our Geoff had quite a few drivers in our time and fuel consumption varied from driver to driver even when driving the same truck.I think Mr.Bewick will agree on that point.No two drivers are the same.I think it is a pity that the skills which were taught when we were young (driving was whole lot more than just turning a steering wheel and pressing pedals)are being lost and will probably disappear altogether in the near future.I suppose that this is the price of progress,if it can be called progress! that’s a matter of opinion.I am retired now,but I do a bit of voluntary work a couple of days a week.I don’t drive a truck,it’s only a sprinter with a little fridge trailer behind it.I go to a potato factory and it’s amusing watching the antics of some of the ‘drivers’ trying to get on to the loading dock.So far I’ve resisted the temptation… but one of these days.

[kr79]

Trucks have 12 16 18 or however many gears so there is a gear for every occasion. 44 ton on flat motorways even at 44ton a 8 speed box would be fine. Through twisting mountainous roads you are going to need more raise the weights more again. IMO at. Standard weights a 12 speed or 13 speed will be adequate.
As the previous poster has said and nmm will probaly agree been an ex press journalist and dealing with the truck builders test staff the best way is get to cruising speed as quickly as possible and umpteen gearchanged ain’t the way to do that.
Look in Europe the swedes who run at the highest gross weights in normal operations. There two major home truck builders have used a 14 speed well 12 plus 2 crawler gears for years.

[v8lenny]

kr79:
Trucks have 12 16 18 or however many gears so there is a gear for every occasion. 44 ton on flat motorways even at 44ton a 8 speed box would be fine. Through twisting mountainous roads you are going to need more raise the weights more again. IMO at. Standard weights a 12 speed or 13 speed will be adequate.
As the previous poster has said and nmm will probaly agree been an ex press journalist and dealing with the truck builders test staff the best way is get to cruising speed as quickly as possible and umpteen gearchanged ain’t the way to do that.
Look in Europe the swedes who run at the highest gross weights in normal operations. There two major home truck builders have used a 14 speed well 12 plus 2 crawler gears for years.

That’s exactly the reason for extra gears. When I’m driving on level ground at 60 tons with Volvo or Scania, I start at 1st high (to save clutch), skip to 3rd low, 4th high, 5th and 6th and I’m at speed limiter. Only 4 shifts needed. But when climbing uphill it’s a different story. If it’s a small hill and I know I need only split then I split but if I know that I have to shift more than split then I shift one main gear, no split, because I lose boost and speed every time I have to lift pedal from the floor.

One thing I don’t understand is why some manufacturers like Volvo and DAF tune their engines so that they drop like a stone when you go past max torque peak, makes it very hard to drive efficiently. Scania and MB have always been much more willing to rev higher.