After reading your article in the Sept. 2018 issue “Dol-Drums: Swapping Disc Brakes Onto a GM 14-Bolt Axle” (bit.ly/2pWGsQx) I am wondering if the parts needed are the same for a 14-bolt semifloat GM axle.
In short, no, the parts are not the same. The semifloating 14-bolt and its big brother the full-floater have little in common other than the name. Like most of the other components on the two axles, the brake brackets with a full-floater and a semifloater are going to be very different. Although the parts we used in that article aren’t compatible with a semifloat 9.5-inch 14-bolt, companies do offer disc brake conversion kits specifically for your axle. Both Lugnut 4x4 (lugnut4x4.com) and TSM Manufacturing (tsmmfg.net) offer disc brake conversion kits for six-lug 14-bolts. Both kits can be ordered with or without calipers brake hoses and several other options, should you choose to source some of that stuff on your own. Both kits are also available with or without calipers with a parking brake function as well. They will fit some 15-inch wheels, but 16-inch wheels are a safer bet. TSM Manufacturing also has a variant that works with eight-lug axles.
There is a year split with the semifloating 14-bolts, so it’s handy to know about what year truck your axle came from if it’s not stock and was swapped in. Keep in mind you’re going to spend about the same money on a disc brake conversion as you would swapping in an entire late-model full-floating 14-bolt that has disc brakes from the factory.