They are expensive to maintain. Sending the brake combination valve off my 77 F150 for a complete rebuild. Folks that do niche work that isn't done anymore can name their price. On the upside they are typically top notch. If all the other brake parts are gonna be new, no sense in not servicing the brains of the system. After 49 years it was probably due.
I enjoy the comfort of my new truck, but also love the quarter windows open, windows down, and the smell of raw exhaust.
Real mechanics are a dying breed literally. There’s very few who can or will fix something anymore. They just replace disposable parts nowadays. I took a standadyne DB4 fuel pump to Bama Fuel Injection recently. They rebuilt it for me (about 1/2 the cost of a factory reman) but those places are becoming more rare. As the older guys retire or die nobody is there to fill their shoes.
