Well,
The way I look at it, it's CHEAP. I mean, what's it take, a few ounces? Besides, the way I do it, I remove the wheel/tire, then I remove the brake drum. That way, I get to inspect all the innards of the brakes etc. It's really not all that hard.
I was just doing a prefight check on the coach, getting ready for few hundred mile trip and, changed the engine oil and filter. Changed the fuel filter, lubed the chassis and all components that needed it. While the coach was in the air, I checked the front wheel bearings for play by grabbing the top and bottom of the front tire(s) and push-pulling those, I could feel play in the right front wheel. The left front was fine.
So, off came the tire and wheel and the drum. I removed the side/knurled plug and, let what would drain, drain. I then removed the six bolts, holding the hub cover on. I then tightened the bearing and, re-installed everything. I refilled the hub with some new 85W-140 gear oil. The entire process took me about an hour, start to finish.
While Freightliner may want you to maintenance your chassis a bit more than some of you would like to, and Cummins or, any other entity might schedule differently, I simply take into account, the time, the miles and what kind of driving was done. I then maintenance it accordingly. And that maintenance never goes over a year between each time.
Scott