Re: [A/S] Mercedes ML 500 and a 34 foot Airstream

[Rick Kunath <k9ao@xxxxxxxxxxx>]

> One of these days the automakers (of serious tow vehicles) will install a
> sway/directional stability control on the tow vehicle which will also work
> with the trailer's brakes.  With Airstream again offering disc brakes on the
> trailer (which would be faster acting than the magneticly actuated drum
> brakes) such a system could be readily implemented. Ford woke up and
> integrated the trailer brake controller into the braking system of their
> full size pickups in 2005.  Sensors could be put on the trailer wheels (the
> directional stability system has already been developed for 18 wheelers) -
> and voila - a major advance in RV towing safety!
> 

Actually, unless I am mistaken, these systems are already available on 
SOB trailers (and needed a lot more with them.) So adding this to an 
Airstream might not be a huge design issue. With the automaker (hello 
Ford?) adding this to the tow vehicle, you'd have a real safety 
breakthrough.


> So far as the Toureg's off road capability is concerned, I have to disagree
> with you.  When VW designed the Toureg, they believed that superior off road
> performance was an important capability for an SUV. So, they bought a Jeep,
> as a benchmark; only to conclude that it was a mediocre off road performer,
> and a poor touchstone. So they set out to design something better.
> 

I suspect the Jeep that was used as a comparison might have been a 
Cherokee or a Liberty. These definitely are not top off-road performers. 
Neither are most SUV-type/style vehicles these days.

The 10-inches of ground clearance the VW has with the air-suspension 
inflated is a big plus, but the breakover angle is not good enough 
because the clearance to the kick panel, and to other under chassis 
areas, is not the 15+ inches that more capable off-road vehicles offer. 
You can't straddle rocks without the high clearance beside the 
differential and higher clearance under the kick panel. Approach and 
departure angles could also be improved, and lots of plastic trim would 
be damaged during obstacle approaches.

I can't imagine a Jeep Rubicon with both axles locked having any trouble 
besting the VW on a difficult course. Not that the VW doesn't offer a 
decent 4WD system, but because of body design, smaller non-aggressive 
tires with insufficient sidewall area and without sidewall traction 
lugs, non low-pressure rims, a less-than 4:1 low-range in the transfer 
case, independent suspension without solid axles (by virtue of how it 
improves ride) limiting articulation, etc. All of this is standard on a 
Jeep Rubicon. Of course it isn't a superb daily driver, and I keep my 
Jeep garaged in northern Michigan some ways from me here, unless it's on 
it's way to Moab.

I am not one for automatic traction control devices in off-road 
situations. More often than not, I do a better job myself of having the 
vehicle in a proper configuration prior to an obstacle. This might 
include locking both diffs, etc. Doing so negates anything a traction 
control system might do, and works far better. The reaction time for a 
traction control system causes safety issues in some situations 
off-road, slickrock is one. The rollback as it operates is really 
disconcerting most times, and dangerous sometimes. ATC vehicles behave 
really strangely when one wheel is elevated. On-road is another thing 
entirely. There it can be a real plus.

Off-reading can be pretty relative. One person's hard trail can be 
another person's (and vehicle's) milk run.

> 
> Since most customers who bought SUVs probably weren't as serious about the
> macho off road performance as the automakers were led to believe (or
> promoted in their advertising - which trickled down to their engineers), the
> modern incarnation of the SUV is becoming a slightly larger Station Wagon of
> old.
> 

They sure are :) and you'd be surprised at how many drivers I see here 
in Michigan slipping and sliding around on the streets because owners 
don't know how to engage the 4WD. One unfortunate woman here a few weeks 
ago dropped her Jeep Grand Cherokee off a freeway bridge in a big 
snowstorm to her death because her husband never taught her how to flick 
the 4WD switch.

> Some time ago, while waiting for some service on my Chevy Silverado pickup,
> several H2 Hummers pulled in for service.  In each case, a petite lady
> driver climbed out!  I asked the service writer if this was common - tiny
> drivers in big broad Hummers.  The answer was Yes, little people do tend to
> go for big Hummers!

LOL, my wife is one of them. But in her defense, she is an awesome 
off-road driver and has done a lot of slickrock crawling with me out in 
Moab over the years. So, she actually does know how to get the most out 
of her Hummer, every bit of it in fact. She's done the Golden Spike, 
Elephant Hill, Hells Revenge, the Shaffer and Burr trails, driven 
extensively in the Maze, Lockhart Canyon, Capitol Reef, the Waterpocket 
Fold, Canyon Rims country, etc. Needless to say, she's my adventure partner!

All this talk about adventures... time for another one, I'd say :)

Rick Kunath
WBCCI #3060