Chalk and Cheese

I find myself with an interesting juxtaposition between my current trucks in Europe and America. In Europe I recently added a MAN TGX to my personal fleet. She is a top specification machine with the XXL cab and a 680HP V8 engine and the 12sp auto box (which I’m driving as a manual). This is very much my dream truck – I have expressed before my preference for MAN vehicles if only because I love the elegance of the design. Over in America I’ve added a truck that I would probably never have considered a month or so ago. This is a Kenworth dating back to 1949, the 521 model. I blame SNR for his enthusiastic youTube review! She has a 250HP Cummins engine and a 14sp Spicer manual box. The cab is basic – no sleeper. Both trucks are 6 by 4’s and there any similarities end!

Let’s start with the cab’s – the driver’s office. The first thing to note is the forward visibility. In the MAN a huge expanse of glass gives an almost unparalleled view of the road ahead (and the scenery) whilst the K521 has two small rectangular windows and the long hood in front serves to hide quite a bit of the road. The next is the sheer size of the MAN cab – it’s not as wide as the US cabover trucks but it is pretty big. The 521, along with its contemporaries like the Peterbilt 281, has a narrow cab not much wider than my car! The layout of the instruments is surprisingly similar in both cabs with the speed and revs being large and easy to read dials placed centrally. MAN have replaced a lot of the other dials with a central information screen. But the key Fuel, oil and Air systems information is still presented on easily read gauges below the main dials. The one error with the design of the K521 dash is the location of the fuel gauge – hidden behind the indicator box on the steering column. Watching a video of a preserved K521 I understand that fuel gauges were also fitted to the tanks and the driver would check the contents as part of his walk around.

The mirrors are a glaring difference between the trucks… In the MAN they are on the edge of the driver’s line of sight making it easy to see traffic overtaking without doing more than glancing. Look at the cab view screenshots below for the K521 – can you see the mirrors? I thought not – It’s a direct result of the narrow cab. In order to see round the trailer, the mirrors are mounted much further out and the driver has to turn their head to see what is coming up behind. It’s interesting to note that the current Kenworth W900 is the same but to a lesser degree because the cab is somewhat wider. Progress isn’t necessarily all good though – those mirrors on the MAN combined with the door pillars create a big blind spot at roundabouts!

Kenworth 521 Cab
Kenworth 521 Cab

Engines and drivetrain – so different and yet… There’s a huge power difference between 250HP and 680HP. In the real world the majority of tractor units purchased in Europe this year will have engines rated around 460HP. For normal trailer loads this is an efficient choice. Having a V8 680HP engine in the real world would be in indulgence unless your truck is going to be employed in real heavy haul work. But in a simulation game we can have such indulgences. With modern trailer sizes and weights the 250HP is low on power. That doesn’t mean that it can’t do the job – it just doesn’t do it as efficiently. The relative efficiency is shown up by the fuel economy figures. The Kenworth is barely averaging 5mpg while the MAN is achieving 6.5mpg with similar loads and that’s despite being over-powered for the job and having to handle the stop start progress through the toll roads system in France!

None of this is a criticism of either truck. They are products of their time. Modern safety and environmental concerns have played their part in truck design as have commercial pressures. The result is that the MAN achieves 1.5mpg better performance with average day to day loads. On real heavy haul the difference between the figures would be larger. I know that some of the current Freightliner Cascadia trucks are turning in around 8mpg in the real world and the real world figures for the MAN are probably in that region too – you have to remember that the fuel use figures are a little compromised by the 20-1 mile / km ratio to real world distances in the game. But the results of my logging in-game performance of older trucks against modern serves to highlight the advances made.

One huge difference in the modern world that the K521 was not built for is the degree of regulation. This is most evident in the gearbox ratios of the Spicer 14 speed – assuming it has been correctly replicated in game. Selecting ratios for the MAN is a choice between best top speed versus best economy and may be guided by which areas of Europe you will do most of your driving in. You might choose longer ratios if you intend to do most of your driving in France and the UK for example whilst lower speed limits elsewhere might cause you to compromise your economy in France to achieve better economy at the lower speed limit in Germany and Austria. Whatever ratio you select, your truck’s maximum speed is limited by law and governed to 90kmh. In American Truck Sim there is a blanket speed limit for trucks of 55mph in California – the K521’s engine runs at economical revs in 12th gear at this speed and I obey the limit – I’m not out there to upset any wandering Smokeys! Come to Arizona and some sections of interstate have a limit of 75mph – she could do that in 14th except that I do a lot of ‘World of Trucks’ jobs and the trucks are governed to a maximum of 65mph (something to do with an impending federal law?). So I’ve never got into 14th to see how fast she can really go. But a fellow owner of this mod claims to have had her up to 109mph and I can well believe it! So, the K521 is geared for a time before regulations.

Driving these trucks is a real mix of experiences. As you would expect, the turning circle of the cabover MAN is far better than the 521 with its conventional layout. As I have discussed before, European truck and bus legislation has been driven by lack of room on the roads and concerns about safety with increased vehicle weights. Latterly, emissions and economy have also played their part in the transport system that we currently have. American legislation is a little less easy to understand in the why’s and the wherefores for me as a European. That emissions law I mentioned refers to noise as well as gases and Health & Safety regulations require that the driver is protected too. So when I climb into Dark of Night’s cab (my MAN TGX) all I hear from the engine is a background murmur. Climb into Greenline Express (the K521) and the sound is deafening. That’s not a fair comparison though – Different eras! Climb into Nightshade or Angel which are both contemporary American trucks and the engine noise is quieter but still more pronounced than their European counterparts. For some of us the sound of a diesel working hard is a joy in itself!
I’ll leave you with images of Greenline Express and Dark of Night…

Greenline Express
Greenline Express
Dark of Night
Dark of Night

…And as a final thought on engines and fuel economy. Today I went out in Nightshade – my Peterbilt 389 – and by luck picked up a load over the same tricky route through California and Nevada that I had driven in the K521 just a day previously. It wasn’t exactly the same – we ran from Bakersfield to Elko rather than Fresno to Winnemucca but the core of the route was the same difficult set of highways. The improvements are illustrated in fuel consumption but also in time. 4.48mpg vs 6.26 for the Peterbilt 389 with a 525HP Cummins N14 Celect engine. But I also covered a third more distance before I needed to take my break because of the ability of the more powerful truck to recover quicker from each delay on the road. That’s around 5 hours saving! The hidden savings of time are much harder to quantify aren’t they… It was great to get up to Elko and hook up with my Ladies team operating out of the garage there 🙂

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