Just a thought.......unless you're putting your truck back into showroom stock condition, where authenticity seems to over-ride current technology, why not add a relatively simple little device that helps you control your brake bias?
Having tried the "everything new but stock" configuration with my trucks brakes, I soon discovered that "anticipating stops and laying back" were just prolonging the inevitable. Even at their very best, a panic stop was going to require some major pressure on the pedal and room to control the inevitable rear wheel lockup. Back in the day, when everyone was running drum brakes and traffic was a whole lot lighter, you were on a more level playing field in relationship to bringing the beasts to a halt. But with todays upgraded braking technology on every vehicle, it became apparent that if I was interested in having a safe driver I'd better make some upgrades.
Now I'm not advocating that every Bolt be shod with discs....if you're putzing along on country roads at stock truck speeds and focused on what you're doing you'll probably be okay. However, it only takes one panic stop that wipes out an $80K Beemer to ruin your day. So to me, maximizing your braking POTENTIAL is paramount whether it be drum/drum, disc/drum or disc/disc.
I'm a FIRM believer in using an ADJUSTABLE proportioning valve in all of the options above and also residual valves where applicable. Drum/drum masters are "supposed" to have built-in valves but who knows for sure on a repop? Any issues I've encountered with setting up an upgraded brake system, have come from trying to use a generic proportioning valve. Especially those supplied in the so-called upgrade kits. Incorporating a $40.00 adjustable proportioning valve in even your drum/drum brake system is going to let you better CONTROL rear wheel lockup. Being the obsessive compulsive person I am (my own admission) I extend the adjustment knob up through the floorboard so I can fine-tune the brake bias according to my load and the road conditions. My own take on ABS. (sorta)
When you're upgrading your brakes with the intention of driving your truck on the modern highway, I'd seriously consider adding a relatively inexpensive adjustable proportioning valve instead of a junkyard proportioning/metering valve. Once you get it dialed in you'll enjoy even more, putting your "Bolt" out on the road.
Dave
