Cruise Control:
i think in some shape or form my question has been answered in a combinations of people posts
as you were.
Come on now, this is TNUK, you didn’t expect a straight answer 
Everyone should have a tag axle Scania V8 and the world would be a better place!.
NB12:
Everyone should have a tag axle Scania V8 and the world would be a better place!.
No thanks, you can poke your Scanias & your tags, I’ll keep my Peterbilt 
NB12:
Everyone should have a tag axle Scania V8 and the world would be a better place!.
OOOOhhhhh dont shake that can of ■■■■. A mighty 143 with the hydraulic tag that had to be lifted on roundabouts/junctions to prevent the crossmember bending.
I’ll keep me 4x2 thank’s. 
newmercman:
NB12:
Everyone should have a tag axle Scania V8 and the world would be a better place!.No thanks, you can poke your Scanias & your tags, I’ll keep my Peterbilt
newmercman They say that they’re going to get some Brit managers over there to show them how it’s done.So your Pete is going to be converted to a 6x2 and if you’re lucky they might put that Scania V8 in it but it’ll probably have to be the 6 cylinder Scania motor instead for extra economy.The only problem is that everywhere you go you might get laughed at.Serves you right.
Carryfast:
newmercman:
NB12:
Everyone should have a tag axle Scania V8 and the world would be a better place!.No thanks, you can poke your Scanias & your tags, I’ll keep my Peterbilt
newmercman They say that they’re going to get some Brit managers over there to show them how it’s done.So your Pete is going to be converted to a 6x2 and if you’re lucky they might put that Scania V8 in it but it’ll probably have to be the 6 cylinder Scania motor instead for extra economy.The only problem is that everywhere you go you might get laughed at.Serves you right.
I’d have no problem with a Scania V8, an old mechanical 14 litre that had been breathed on by Feather Diesels or the Dutch or Swedish tuners would be very nice, the midlift wouldn’t worry me either, but if they tried to put that silly little Topline cab on I’d smash the [zb]er up on the first trip 
Just as an aside, my 550hp CAT bulldozer engine puts out 1850nm of torque, I bet the six pot Scania could put that to shame
newmercman:
Carryfast:
newmercman:
NB12:
Everyone should have a tag axle Scania V8 and the world would be a better place!.No thanks, you can poke your Scanias & your tags, I’ll keep my Peterbilt
newmercman They say that they’re going to get some Brit managers over there to show them how it’s done.So your Pete is going to be converted to a 6x2 and if you’re lucky they might put that Scania V8 in it but it’ll probably have to be the 6 cylinder Scania motor instead for extra economy.The only problem is that everywhere you go you might get laughed at.Serves you right.
I’d have no problem with a Scania V8, an old mechanical 14 litre that had been breathed on by Feather Diesels or the Dutch or Swedish tuners would be very nice, the midlift wouldn’t worry me either, but if they tried to put that silly little Topline cab on I’d smash the [zb]er up on the first trip
Just as an aside, my 550hp CAT bulldozer engine puts out 1850nm of torque, I bet the six pot Scania could put that to shame
I never did rate those old four stroke sloggers .But if your figures are right ? ? your CAT would need to sustain it’s max torque of 1,369 lbs/ft all the way up to 2100 rpm to give that 550 bhp ! ?.But if you’d have had the old 16V71 two stroke in it that I had in the first types of wagon (built from 1970-1980 while Scania and Volvos engineers were still learning how to make a truck go) that I ever drove you’d have had around 1800 lbs/ft not 1850 nm but most engines have around a 10% torque drop at max power revs or the power would keep rising and that’s why that Detroit ‘only’ gave out around 630 horses .But then we could have gone for the turbocharged version if they had decided that it was’nt fast enough without turbocharging already .I’d just ask your guvnor to put a 12V71 in it with turbocharging instead of that old 14 Litre V8 Scania mill and then you’d know why you need a 6x4 driveline as well
Carryfast:
newmercman:
Carryfast:
newmercman:
NB12:
Everyone should have a tag axle Scania V8 and the world would be a better place!.No thanks, you can poke your Scanias & your tags, I’ll keep my Peterbilt
newmercman They say that they’re going to get some Brit managers over there to show them how it’s done.So your Pete is going to be converted to a 6x2 and if you’re lucky they might put that Scania V8 in it but it’ll probably have to be the 6 cylinder Scania motor instead for extra economy.The only problem is that everywhere you go you might get laughed at.Serves you right.
I’d have no problem with a Scania V8, an old mechanical 14 litre that had been breathed on by Feather Diesels or the Dutch or Swedish tuners would be very nice, the midlift wouldn’t worry me either, but if they tried to put that silly little Topline cab on I’d smash the [zb]er up on the first trip
Just as an aside, my 550hp CAT bulldozer engine puts out 1850nm of torque, I bet the six pot Scania could put that to shame
I never did rate those old four stroke sloggers
Carryfast you really do need a bit of of therapy my old son — Why arn’t the roads of the UK & Mainland Europe choked with GM 2 strokes ? Why — because they are unmitigated bags of S**t You’ll be trying to convince us to vote Liberal Democrat next !!! Keep your elbows in Bewick.
Carryfast you really do need a bit of of therapy my old son — Why arn’t the roads of the UK & Mainland Europe choked with GM 2 strokes ? Why — because they are unmitigated bags of S**t You’ll be trying to convince us to vote Liberal Democrat next !!! Keep your elbows in Bewick.
[/quote]
That’s exactly what all the unfortunate drivers and I used to say about all those wagons which were still left on the roads of Britain fitted with Gardners when I overtook them with the heaps that I drove on the council But the roads of Mainland Europe were never choked with Gardner powered heaps at any time probably because they would have got a bit upset with all those British wagons blocking up the foothills of the alps.But unlike Gardner powered stuff there just might have been a few Detroit powered Kenworths running over there at 38 tonnes.And the Dutch seemed happy enough with their FTF 's.
Yeah you’re right it is lbs/ft not nm 
Carryfast I share your admiration for the screaming Jimmies, but nowadays they’re only good for entertainment value, they weren’t the best at reliability, fuel consumption was scary & for the size of the engine they wouldn’t pull the skin off a rice pudding Legislation never killed the two stroke (except recently with the motorbikes) the free market was responsible for their demise, people stopped buying them in favour of the turbo sixes from ■■■■■■■ & CAT, this led to a major rethink at DD & the 60 series was born.
As for Gardners in Europe, they were hard to get in a British lorry, waiting lists were years long, so the continentals had to suffer the engines that people had substituted for Gardners, namely the Leyland Group engines. The free market also killed Gardner, much the same as it did to DD & the two stroke, nobody wanted them as they were behind the times, the only difference was that cash rich DD had the ability & desire to develop a conventional engine, the boys at Patricroft by their short sighted attitudes put a stop to this & signed their own death warrants as a result.
newmercman:
Yeah you’re right it is lbs/ft not nmCarryfast I share your admiration for the screaming Jimmies, but nowadays they’re only good for entertainment value, they weren’t the best at reliability, fuel consumption was scary & for the size of the engine they wouldn’t pull the skin off a rice pudding
As for Gardners in Europe, they were hard to get in a British lorry, waiting lists were years long, so the continentals had to suffer the engines that people had substituted for Gardners, namely the Leyland Group engines. The free market also killed Gardner, much the same as it did to DD & the two stroke, nobody wanted them as they were behind the times, the only difference was that cash rich DD had the ability & desire to develop a conventional engine, the boys at Patricroft by their short sighted attitudes put a stop to this & signed their own death warrants as a result.
But it was a developed turbocharged version of the Leyland 680 which built DAF’s well earned reputation with the 2800-3600 range and on to the 95 if I remember right and I always preferred the DAF to Volvos and Scanias.But as for the Detroit it was it’s specific power and torque outputs which were it’s main advantage.The principle of twice the amount of power strokes per revolution of the engine is as good today as ever which is why they still use two strokes in ships.But as a comparison the 8V92 gave out around 400+ horse from 12 litres at the same time that the 14 Litre ■■■■■■■■■■■■■ F12, and the 11.6 Litre DAF were only giving out around the same,or less,outputs as the 9.0 Litre 8V71 even in non turbocharged form.With up to date turbo charging and fuelling I’d guess that the 60 series would be outclassed.But it would’nt be the first time that GM had made a mistake.
Carryfast:
But it was a developed turbocharged version of the Leyland 680 which built DAF’s well earned reputation with the 2800-3600 range and on to the 95 if I remember right and I always preferred the DAF to Volvos and Scanias.But as for the Detroit it was it’s specific power and torque outputs which were it’s main advantage.The principle of twice the amount of power strokes per revolution of the engine is as good today as ever which is why they still use two strokes in ships.But as a comparison the 8V92 gave out around 400+ horse from 12 litres at the same time that the 14 Litre ■■■■■■■■■■■■■ F12, and the 11.6 Litre DAF were only giving out around the same,or less,outputs as the 9.0 Litre 8V71 even in non turbocharged form.With up to date turbo charging and fuelling I’d guess that the 60 series would be outclassed.But it would’nt be the first time that GM had made a mistake.
I defer to your superior knowledge of the two-stroke, I just think they make a nice noise what you say all makes sense, maybe the two-stroke could’ve been a better engine with suitable development, the fundamentals suggest it could, unfortunately the buyers don’t want to be guinea pigs while they sort the problems out, hence the already reliable in-line six became the only option, save for a few vee engines.
Carryfast:
renaultman:
Carryfast:
renaultman:
Carryfast:
renaultman:
Carryfast:
newmercman:
My 6+mpg is to the US gallon, that’s 3.72 litres & around 20% smaller than an imperial gallon, so my mid 6s are high 8s, that’s at an average speed of 64ish mph & to average that speed my needle has to go a lot further round the clock on a regular basis, my Pete is about as aerodynamic as a filing cabinet with the drawers pulled out, so it’s gearing has a big effect, I also hit hardly any traffic, even Chicago & New York are fine in the middle of the night & that’s when I try to hit them & I run at 36.3tons with 550hp so unless I’m in the mountains I don’t work the engine hardly at all, that all helps no end when you’re filling the tanks. If I had better aerodynamics, like a euro spec cabover & only one drive axle I could add 20% to that figure easily, while I’m a big fan of the American truck, my Pete in particular, it’s horses for courses, they are perfect over there, but would be about as much use as mudflaps on a tortoise over hereIn the context of a fuel economy comparison I’d say that does’nt seem to add up in favour of a 4x2 or 6x2?.You’re running a 550 horse truck,at faster speeds,which is less aerodynamic,and which has a 6x4 driveline.But you’re already getting around the same return on fuel consumption as a euro wagon which already has that 4x2 or 6x2 configuration.What you do seem to have made the case for is plenty of power,high gearing,high speeds and work the engine less and fit it with a 6x4 driveline.
It’s just a shame that those yanks would’nt let me work there all those years ago.
Trust me
6x4 will almost always be less economical than 6X2, if everything else is equal, think about it? all them gears and shafts to turn, they all require energy, plus the rolling resistance of the extra tyre. The most ecomomical set up, is the twin steer,but the weight and traction costs, outweigh the advantages. Also except for going up hill, a twin steer, has always given me the most confidence on slippery corners etc. (4 wheels to point you in the direction you want to go)And that’s why I’d prefer an 8x4 rigid pulling a 45 foot drawbar trailer.Four wheels to point you where you’re going,two axles to drive it along the road and drawbars don’t jacknife like artics can.But exactly what do the actual figures say if we compare that artic using the twin steer unit if we compare it with that yank 6x4 unit which can manage around 8 mpg running at yank speeds.It’s the figures which prove the case not some unfounded theory which seems to exaggerate the extra transmission loads in using double drive.
Can’t do the figures for American trucks, but I’ve run beside 6x4s in this country, they’ve all been horrendous on fuel. Also (I’m showing my age here) The difference in economy between twins and singles is well documented, there’s even a difference between Supersingles and normal tyres. Ever wonder why racing cyclists have razor thin tyres? The more rubber you have on the road, the more friction/rolling resistance you have working against you.
I bought my own fuel, for 20 years, running max gross, doing approx 100,000 miles a year, believe me, It’s not all theory
It’s not so much an issue of rubber because we’re talking about the difference between 6x2 versus 6x4.But if we want less grip then everyone would have ditched double sets of rear wheels for singles.But in the context of trying to provide traction and grip at the unit’s drive axle/s and to avoid jacknifing it’s more grip which is needed not less and you can’t cut down on tyre size much if you’re imposing high weights on them wether twin or single.But a heavy haulage Euro type 6X4 is’nt the same by way of comparison with a typical yank 6x4 general haulage wagon and those operators using double drive rigids here on general work would never be able to make the job pay if there was that big a difference?.
Where’s here?
I don’t know of anyone running double drive units around here .Here means England not the States and rigids are’nt units.However if I get started on my own doing traction work or whatever with artics I’ll try to use one of those yank 6x4 units which as we’ve been told by someone who uses one can manage around 8 mpg running around at 65 mph or more.It’s obvious that hardly anyone here in England is using double drive units because we’ve seen them all over the news for a week stuck and jacknifed in a few inches of snow
if I get started on my own doing traction work or whatever with artics
I should have known 
renaultman:
Carryfast:
renaultman:
Carryfast:
renaultman:
Carryfast:
renaultman:
Carryfast:
newmercman:
My 6+mpg is to the US gallon, that’s 3.72 litres & around 20% smaller than an imperial gallon, so my mid 6s are high 8s, that’s at an average speed of 64ish mph & to average that speed my needle has to go a lot further round the clock on a regular basis, my Pete is about as aerodynamic as a filing cabinet with the drawers pulled out, so it’s gearing has a big effect, I also hit hardly any traffic, even Chicago & New York are fine in the middle of the night & that’s when I try to hit them & I run at 36.3tons with 550hp so unless I’m in the mountains I don’t work the engine hardly at all, that all helps no end when you’re filling the tanks. If I had better aerodynamics, like a euro spec cabover & only one drive axle I could add 20% to that figure easily, while I’m a big fan of the American truck, my Pete in particular, it’s horses for courses, they are perfect over there, but would be about as much use as mudflaps on a tortoise over hereIn the context of a fuel economy comparison I’d say that does’nt seem to add up in favour of a 4x2 or 6x2?.You’re running a 550 horse truck,at faster speeds,which is less aerodynamic,and which has a 6x4 driveline.But you’re already getting around the same return on fuel consumption as a euro wagon which already has that 4x2 or 6x2 configuration.What you do seem to have made the case for is plenty of power,high gearing,high speeds and work the engine less and fit it with a 6x4 driveline.
It’s just a shame that those yanks would’nt let me work there all those years ago.
Trust me
6x4 will almost always be less economical than 6X2, if everything else is equal, think about it? all them gears and shafts to turn, they all require energy, plus the rolling resistance of the extra tyre. The most ecomomical set up, is the twin steer,but the weight and traction costs, outweigh the advantages. Also except for going up hill, a twin steer, has always given me the most confidence on slippery corners etc. (4 wheels to point you in the direction you want to go)And that’s why I’d prefer an 8x4 rigid pulling a 45 foot drawbar trailer.Four wheels to point you where you’re going,two axles to drive it along the road and drawbars don’t jacknife like artics can.But exactly what do the actual figures say if we compare that artic using the twin steer unit if we compare it with that yank 6x4 unit which can manage around 8 mpg running at yank speeds.It’s the figures which prove the case not some unfounded theory which seems to exaggerate the extra transmission loads in using double drive.
Can’t do the figures for American trucks, but I’ve run beside 6x4s in this country, they’ve all been horrendous on fuel. Also (I’m showing my age here) The difference in economy between twins and singles is well documented, there’s even a difference between Supersingles and normal tyres. Ever wonder why racing cyclists have razor thin tyres? The more rubber you have on the road, the more friction/rolling resistance you have working against you.
I bought my own fuel, for 20 years, running max gross, doing approx 100,000 miles a year, believe me, It’s not all theory
It’s not so much an issue of rubber because we’re talking about the difference between 6x2 versus 6x4.But if we want less grip then everyone would have ditched double sets of rear wheels for singles.But in the context of trying to provide traction and grip at the unit’s drive axle/s and to avoid jacknifing it’s more grip which is needed not less and you can’t cut down on tyre size much if you’re imposing high weights on them wether twin or single.But a heavy haulage Euro type 6X4 is’nt the same by way of comparison with a typical yank 6x4 general haulage wagon and those operators using double drive rigids here on general work would never be able to make the job pay if there was that big a difference?.
Where’s here?
I don’t know of anyone running double drive units around here .Here means England not the States and rigids are’nt units.However if I get started on my own doing traction work or whatever with artics I’ll try to use one of those yank 6x4 units which as we’ve been told by someone who uses one can manage around 8 mpg running around at 65 mph or more.It’s obvious that hardly anyone here in England is using double drive units because we’ve seen them all over the news for a week stuck and jacknifed in a few inches of snow
if I get started on my own doing traction work or whatever with artics
You should have known?.But you might have got that a bit out of context?.It’s in the context of traction work or whatever other type of work using artics.Traction work usually means pulling other firm’s trailers as a subby whereas if you’re using a trailer of your own or rented by you then it’s not traction work.Maybe I should have known that someone might not get the difference But if it was some other issue that you should have known that I don’t maybe it would have been a bit clearer if I’d said I’d ‘prefer’ to use a yank 6x4 unit .It’s more likely that the problems of getting hold of one in euro spec would stop that not the economics.
Carryfast, its obvious you are a big fan of the DD 2 stroke, but they did in all shapes and sizes have reliability issues. Remember the gvw here in the States has always been less than the U.K. Todays 6x4s and Tandem axle trailers (53 ft) max weight is 80000lb 36,400kg 3+2, the 4x2 and tandem trl 73000lb 33,000kg.
They had to be hard work to drive on any work other than over the road, just like a volvo F7 with the 6.7l, 8 spd + splitter 8x4 tipper running at 30,480kgs, high revving with little or no torque curve.
As newmercman said, the reliability of the CAT, along with ■■■■■■■ and later DD series 60
which was based on a tractor engine from John Deere put the 2 stroke to bed.
Since 93, my experience has been with ■■■■■■■ m11, m11E, isx 15l and my favorite 14l
red top 525, all of which were good motors; DD 11.7l non electronic series 60 the first and
probably the best, along with 12.3 and 12.7l updated versions which I found lacking in power and thirsty compared with any of the ■■■■■■■ motors.
My experience with CATs is limited and any comparrison would be unfair, and as they no longer make CAT engines I will leaave that to Newmercman. This year should be intresting
as we will find out what Navistar will produce from a combo of Cat and MAN engines and parts there of!
The best engine in North America at present in my opinion is the Volvo D13 and previous D12, which is also shared with Mack. I have not driven the 2010 SCR version yet or any other builders 2010 so can not comment on those.
Let’s, not forget in those days DD were owned by GM and most of their production went into their own products, GMC’s and Whites.
Cheers Paul
Paul John:
Carryfast, its obvious you are a big fan of the DD 2 stroke, but they did in all shapes and sizes have reliability issues. Remember the gvw here in the States has always been less than the U.K. Todays 6x4s and Tandem axle trailers (53 ft) max weight is 80000lb 36,400kg 3+2, the 4x2 and tandem trl 73000lb 33,000kg.
They had to be hard work to drive on any work other than over the road, just like a volvo F7 with the 6.7l, 8 spd + splitter 8x4 tipper running at 30,480kgs, high revving with little or no torque curve.
As newmercman said, the reliability of the CAT, along with ■■■■■■■ and later DD series 60
which was based on a tractor engine from John Deere put the 2 stroke to bed.
Since 93, my experience has been with ■■■■■■■ m11, m11E, isx 15l and my favorite 14l
red top 525, all of which were good motors; DD 11.7l non electronic series 60 the first and
probably the best, along with 12.3 and 12.7l updated versions which I found lacking in power and thirsty compared with any of the ■■■■■■■ motors.
My experience with CATs is limited and any comparrison would be unfair, and as they no longer make CAT engines I will leaave that to Newmercman. This year should be intresting
as we will find out what Navistar will produce from a combo of Cat and MAN engines and parts there of!
The best engine in North America at present in my opinion is the Volvo D13 and previous D12, which is also shared with Mack. I have not driven the 2010 SCR version yet or any other builders 2010 so can not comment on those.
Let’s, not forget in those days DD were owned by GM and most of their production went into their own products, GMC’s and Whites.
Cheers Paul
Thanks for that Paul but there often seems to be a lot of confusion by those who were’nt very familiar with those motors as to it’s reliability and/or it’s power band.But if you’re comparing something like the 6V53 or the 6V71 with something like a 12 or 14 litre + ■■■■■■■ etc etc then you’d be right but that’s an unfair comparison as it’s obvious that a 7 litre or less non turbo motor is going to be underpowered and overstressed and Bedford were actually using the 6V71 at 32 tonnes here.Compare like with like on capacity and then the case becomes a bit clearer.I’ve been around those motors when they were in service for long enough to know that their reliability and reputation was ok and no worse than CAT or ■■■■■■■ motors and probably better.It’s also easy to mistake that buzz saw engine note for the actual revs of the engine when in fact it’s just turning over at around the same revs as that ■■■■■■■ or CAT was delivering it’s max torque or power at.As an example the ones that I was familiar with developed their peak torque at around 1,200 rpm and peak power at around 2,100 rpm and in the case of the 16V71 and probably most other 71 series motors it’s specific torque output ,which is a similar engineering comparison to BMEP,was around 100 lbs/ft per Litre WITHOUT any turbo charging.So now are they going to say that a ■■■■■■■ or a CAT could match that? and there were plenty of premium manufacturers like KW,Pete and Freightliner,during the two stroke’s production life,that fitted it to customer order which because it was usually the most powerful option available meant plenty of orders and happy drivers especially with those decent 13 speed fuller gearboxes.
Carryfast, you certainly make some good points, perhaps the downfall of the 2 stroke was GMs lack of investment to modernise and improve their products, just like Gardner!
If you were on their payroll, then we might have them as an option today.
Back to tag axles, before leaving the U.K. early 90s I ran 3 6x2 units, 1 as a 3+2 at 38000kgs, 2 3+3 at 38000kgs. All units were twin steer/ lift, with ist axle lift on tri axle trls. A friend of mine ran a 2+3 set up, and in my opinion the 3+2 was more stable and handled better. The 3+3 was obviously betterthan both, but the extra drag on the trl 3rd axle was unbeliveable, and had an impact on MPG. Nowadays the GVW has changed, so at 44000kgs its 3+3. I only drove 1 tag axle, a Scania with dual rear wheels and it seemed to nod alot, and the overhang when they were lifted for tight turns could catch you out. It was
horses for courses, but at least there were options.
Here in the States there are a few 4x2s with long wheel base and twin wheel pusher axles on them, everything else is 4x2 single axle, or 6x4 tandem axle (twin screws).
The 5 axle combos, run at 80000lb gvw (36400kgs)with a 41ft Fifth wheel to centre of trailer axle limit for interstate highways. Trailer length is 53 ft, but no overall limit. In order to get your axle weights right you have to slide your trailer axles no further than that figure of 41ft, with a little more tolerance from a sliding fifth wheel. It really is an out of date system. Super singles are starting to appear on trailers, with promises of fuel and weight savings, and on some 6x4 units, thats because the drive axle max weight is lower than the U.K… I have driven all variations and found the super singles on tractors, at least as fitted so far seem to run in the tramlines of the duals (twin wheels). The aspect ratio of the rim needs to be changed to give a greater axle width, as side by side the dual wheels on the same tractor sits wider.
To be honest I would like to see the gvw raised to 100,000 lb (45500kgs) on six axles, with
a a 6x2 dual wheel tag axle tractor matched to a tri axle (fixed) ist lift 53 ft trailer fitted with super singles. That way you will get max pay load, and stability due to better balanced axle loads.
I don’t know about 100000lb, it makes sense, especially if there’s a bit of tolerance on the axle weights, as you know getting 80000lb is only possible if you max out your axle weights, I’ve not had too much trouble getting it all right & I’ve had a few that scaled out at 79990, my trailers wheels have been anywhere but at 41ft though, luckily I have Pre-Pass so I stay out of most scales, but the Ports of Entry in the western states need careful planning so that full tanks don’t put you over.
My thoughts on CAT engines are mixed, they pull well, they’re reliable, but they’re not the most economical & they’re unrefined, not a smooth running engine at all, my first Pete had a 60 series @ 500hp, that never had the pull of the CAT but was a nicer drive, the Jakes sounded good too. before that I had a Volvo with the D13, it was a lovely motor, very economical, powerful, I don’t know about reliability as it was brand new, that’s about it for my North American experience.