Hey Sitec, our habitat is 5.3m and almost 2.4m wide. The width is from the rubber fender wells on the front tires. The box length hangs over the rear of the chassis about 300mm (the bottom of the 45 degree angle is at the end of the chassis). Once we got the 385/65 R22.5 tires on our height of the chassis is around 39". For some reason the GVWR of a 1017 and 1120 are the same at 12,000kg (I thought the first digits were the weight rating). Our cab is definitely narrower than the pictures I have seen of the 1017's, but still seems large. Although a little late for me, it would be interesting to see the chassis/axle differences between these 2 trucks as our plans are essentially a land circumnavigation, hope we made the right choice (they all seem pretty robust but I am new to medium duty trucks). We are getting right around 13mpg which I am pretty pleased as the 1120 is full time 4WD. After our cab upgrades and new higher sidewall tires the ride is actually pretty good, not sure how it compares to the 1017. I keep mentioning the 1017 as it was the other truck I was looking into. I bought our truck sight unseen, so was unable to visually compare the 2.
When you say the 1017's have larger engines I am a little confused (happens often). I think the 17's (though not the 917 which uses the OM366A) use the OM352A which I also think is a 352 c.i. inline 6. Our truck has a OM366LA, so a 366 c.i. inline 6. I sort of figured it was just a slightly larger displacement of the OM352, is the block lighter? Now your 1222 has the much larger V6 and they even offer a larger V8. Given that our truck is the only MB cab over truck I have personally seen anything I think I know is just internet reading.
When you say the 1017's have larger engines I am a little confused (happens often). I think the 17's (though not the 917 which uses the OM366A) use the OM352A which I also think is a 352 c.i. inline 6. Our truck has a OM366LA, so a 366 c.i. inline 6. I sort of figured it was just a slightly larger displacement of the OM352, is the block lighter? Now your 1222 has the much larger V6 and they even offer a larger V8. Given that our truck is the only MB cab over truck I have personally seen anything I think I know is just internet reading.
Your setup sounds really good, but now it's taking shape you would probably agree that you wouldn't go much bigger with the box on your platform. The chassis on the 1222 is taller coming in at around 48/50", and I've settled at a 6m long body (that's 94" tall giving a total height of approx 142" or 3.6m) as it's what I have, but could have gone longer. Adding a bit of height, and 100mm in width suddenly makes for a bigger handful. I've driven a few 1120's but not for a long time, so it'll be interesting to sight Traveling Babo (the incoming 1120) and park it beside the 1222 and see how they compare. I might be surprised at how little difference there is!