Chris, There will be a lot more electrically actuated components on future vehicles. The planned introduction of a high voltage electrical system (I can't recall the voltage off hand) is the handwriting on the wall. This technology is much more compatible with computer control, but with 12 volts it is hard to build any powerful direct electrical actuators, hence the higher voltage level. Meanwhile, we'll have to live with the old electrically activated drum brakes. The disk brakes on the late 70's Airstreams were less than great design, and of course required a vacuum tank to provide the power boost to generate sufficient pressure to the disk brake caliper pistons. If you stay with disk brakes, you are going to have to generate some very high forces (and pressures) to make them work. Drum brakes do not require high actuating forces to function. Rather, they get their stopping power from the force generated by the friction of the forward brake shoe against the drum, which is then transmitted to the rear shoe. As goofy as the electromagnet actuated drum trailer brakes are, the do work very well and are simple. If a new technology replaces this, it will have to be simple, reliable and modest in price - a tall order for any product. Obviously, if one extends the hydraulic brake line from the tow vehicle to the trailer, and then the line breaks, the tow vehicle's brakes go with it. Thus any safe hydraulic system will have to isolate the tow vehicle's hydraulic system from that of the trailer, yet couple them so far as changes in pressure on the tow vehicle are concerned. Until such a design is available, connecting the tow vehicle hydraulic brake system directly to the trailer brake system is a dicey proposition. Oliver Filippi To unsubscribe or to change to a daily Digest, please go to http://www.airstream.net/vaclist/listoffice.html If replying back to this message, please delete all the unnecessary original text from your reply.
