Kenworth Trucks Discussion Thread

[J.Random]

Napkin math: 11R22.5 will give you roughly 500 revs per mile (differs from tire to tire, changes with temperature, etc.).
~$gcalccmd
> 62/60*500*2.28
1178
> 62/60*500*2.16
1116
> 62/60*500*2.85*.78
1148.55
> 62/60*500*2.64*.78
1063.92

At this point you can just say "eh, anywhere between 60 and 65 you're good" (probably even 55 to 65, considering that IDP engines are downrevved) instead of pretending that there's some magic number.

[rookie_one]

Volvo also list 2 differential ratio for it's XE packages, and they still program them to shift to twelfth gear at 62 mph no matter the RPM(except for the adaptative loading programmation, but that's another debate), it's not farfeteched to believe that Detroit did the same thing with IDP

That said in Volvo case, the specs call for 275/80R22.5 tires if i'm not mistaken, while i'm not sure about DEtroit on that part (that said when I calculate, 11r22.5 is slightly under 500 rev/mile)

[EllieODaire]

Yeah the key with the integrated Detroit Powertrains is top gear low RPM. My 2022 Cascadia with the Gen 5 DD15 and an overdrive DT12 sits at 1000 RPM at 55mph in 12th, up to 1200 RPM at 65mph. In my experience for the first 6000 miles 58 to 62 get me the best fuel economy (the truck doesn't have the full aero package so that's only around 7.5 to 8mpg when fully loaded), though it barely drops at all at 62 or 65. 55mph can generate better fuel numbers under a light load, but with anything remotely heavy the truck downshifts to 11th on even the smallest hills and counteracts the advantage you gain driving 55 instead of 58.

Also 62mph is 100kph, which is why it is such a popular number for people to govern trucks at or for OEMs to target for the fuel economy sweet spot. 105kph (65mph) is the max speed for trucks that operate in eastern Canada, so 100kph is a good cruising speed to aim for for trucks sold on the North American market, as even a lot of US carriers operate their trucks governed at 65 so they can do cross-border runs if they come up.

[rookie_one]

btw @EllieODaire , since you mentionned having a Gen 5 DD engine, any chance of you managing to talk to someone at Freightliner or Detroit and get the torque curves for the DD13 Gen5 and DD15 Gen5 ? They don't have all the curves on DemandDetroit Website

[causa67]

Nice the W900 but quite fragil. I was several times by one mine in Colorado, south of Denver, to pick cargo. Most with Peterbilt 389 and 579 and not problems. Yesterday I was there with my W900(my only Kenworth)and very fast damage began to come by this dirty roads. And driving at not more of 10 mph. Default version(Vanille)with any mods.

[EllieODaire]

btw @EllieODaire , since you mentionned having a Gen 5 DD engine, any chance of you managing to talk to someone at Freightliner or Detroit and get the torque curves for the DD13 Gen5 and DD15 Gen5 ? They don't have all the curves on DemandDetroit Website

This is the only one I've seen: https://demanddetroit.com/engines/dd15-gen-5

[rookie_one]

shame, I wonder who we could talk with to obtain all the missing curves

[1948LJMack]

I was thinking for the game, I am surprised that Kenworth only allowed SCS to have the W900 with just the newer dash and the single pane windshield. The truck had an optional two pane windshield and due to the history of the truck, they could have added dashboards from the older generations of the W900 and the doors as well to represent the history of the truck. In the 1990s, Kenworth had the flat dashboard in the W900. The daylight doors didn't come out until about 1999 or 2000. Even on How It's Made, we see the time when Kenworth was introducing the daylight doors. I would love to see Kenworth pay SCS to licence the older model W900 dating back to I think 1986 or 1987. It would be a nice extension to the current one in the game.

[JoeAlex23]

That's not how licenses work, it's SCS that has to pay the manufacturers to have a truck in game, also, the W900 we have in game is a 2015 model.

[TruckerKid]

*pre-2007, lack of DEF tank and the design of the exhaust system indicate the truck is designed from a model before the 2007 DEF requirement on production trucks.

Pre-2007 DEF requirement
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Post 2007 DEF requirement
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