Disc Brakes in 1977?

[ericjan2]

I was reading my 1977 AS manual. There is a large section regarding the disc brakes! It was my understanding that the 70's Airstreams came with minimal shoe brakes that were only engineered to stop the rig if it breaks away from the tow vehicle. Am I wrong here? Were disc brakes an option in 1977? Thanks, Eric

[4RXLA]

The Excella-vac disc brakes were an option on the International and standard on the Excella 500 in 1977. The system was operated by a vacuum actuator pump that was located on the A-frame just behind the propane tanks and vacuum was provided by the tow vehicle. A vacuum hose from the trailer to tow vehicle made the connection. This was before anti-lock brakes were used on vehicles. The trailer brakes could stop both the trailer and tow vehicle.

[AlbertF]

Originally Posted by ericjan2

I was reading my 1977 AS manual. There is a large section regarding the disc brakes! It was my understanding that the 70's Airstreams came with minimal shoe brakes that were only engineered to stop the rig if it breaks away from the tow vehicle. Am I wrong here? Were disc brakes an option in 1977? Thanks, Eric

From what I’ve seen, the drum brakes used on new Airstreams are essentially the same as those used in the 1970s. At the time, those 2”x12” drum brakes were oversized relative to gvwr and the brakes used by other manufacturers.

Today, perhaps they are not really oversized, at least when we consider that there are now 10000 lb GVWR Airstreams with only two axles and four brakes.