Note that the SMB web site changed (this week?) for the 2008 SMB 4x4 (excerpt below).
In summary, I think it means that you will get a better system but you will pay for it. Mandatory 17" tire upgrade + Hella system = net $3k additional.
-Mark
Begin excerpt from
http://www.sportsmobile.com/4_4x4sports.html
Because Ford redesigned the van's front end, it was necessary for Sportsmobile West to redesign the 4x4 front axle. This upgrade consists of a new casting, larger knuckles, hub and F550 rotor. Ford also beefed-up the calipers. The calipers, rotors and ABS sensors are Ford factory parts, making this system easier to service.
These changes are comparable to a $2,000 upgrade.
However, redesign causes two other issues:
• With Sportsmobile West's larger brake rotor, the factory 16" wheel will not fit. Sportsmobile West 4WDs will require 17" wheels, which are available through Sportsmobile.
• Ford's factory tire monitoring system is not adjustable. It is set for 55 PSI front and 80 PSI rear. If the larger tires are designed to run different PSI, then an after-market tire monitoring system will be required.
We recommend the Hella Remote Monitoring System. This system is adjustable, and if a tire is low it will tell you how much and which tire. It also monitors the temperature of each tire. The Ford monitoring System only tells you when a tire is low. The Hella System is available from Sportsmobile for $475 installed for a set of 5. Without this system, the Ford factory tire monitoring system will not function.
end excerpt