Mercedes-Benz Actros gearboxes - I don't understand them

[Louella]

So, I was shopping for a Mercedes-Benz truck, and trying different things out, before deciding on a configuration to buy for my fleet of trucks.

What I found was, the most expensive gearbox, the 16speed Powershift G280-16R, wasn't really suitable for what I was wanting.

At 80km/h, the engine was running at 1400rpm in top gear. That just didn't seem right. Felt way too high rpm.

So I tried the 12speed Powershift G330-12R, and was getting something like 1100rpm in top gear at 80km/h. Which seemed about right, given that all the available engines say their peak torque is at 1080rpm. So that was the gearbox I decided on for my fleet.

Now there's also a 6-speed gearbox, which has a torque multiplier, and I've been assuming those are really for the super-heavy cargoes, where you won't be going fast anyway.

But what are these 16-speed gearboxes for ? They don't seem at all suitable for the autobahn.

[xXCARL1992Xx]

they are meant for the Actros SLT, where high speed isnt reached at all, it is more to get the load moving then to speed up the load, the Actros SLT can move up to 250t, so the gearbox have to be capable to pull this kind of weight

[Eugene]

It's not just the gearbox that matters, it's combination of gearbox and differential ratio. Not to forget the engine power
Generally, the higher diff. ratio (3.xx - 4.xx) is better for heavy haulage. Plus, the more gears you have in your gearbox, the easier it is for truck to start moving with heavy cargos. As Carl said, it's designed for up to 250 tons, which we dont have in game.

To ease it down:
6 speeds are for lightweight cargo. (dont forget: less powered engine will struggle with such gearbox)
12 speeds for general cargo (weak engine needs higher diff ratio, powerfull engine needs lower diff ratio)
16 speed are for heavy haul

[dsf.fernando]

So which transmisison would give me the best fuel economy if i plan to haul cargo in the 15-25t range? The Powershift G330-12R or the 6-speed with retarder?

[Taron]

What about 12+2 gearboxes @dsf.fernando ?

[dsf.fernando]

IIRC only Volvo has 12+2 transmissions in the vanilla game

[w1lb3r1]

Scania has too 12+2

[impetoCZ]

Allison 6-speed has no delay when changing gears - perfect for heavy duty but not economical for highways. I use to have standard 12-speed gearbox + bigger wheels on truck - you can reach higher speed with lower rpms.