I did the swap of my OBS master cylinder to a NBS master cylinder. 1999 2 door Tahoe 4x4. 3.42 gears, 35in KM2's
Part of my 4 month Tahoe Overhaul where my goal was to turn the Tahoe into a reliable DD, mechanical-wise, as if it were a new Tahoe. Example: Be able to go 80mph on the highway and sit in stop and go traffic at 110* and not have any mechanical or drivetrain problems.
Parts:
-2001 Chevrolet Silverado 5.3L 4X4 Master Cylinder; Vacuum Boost. Brand:AC Delco. Part Number: 18M1159 . $101 at O'Reilly
-Brass Adaptor. Autozone. Brand: AGS. Part Number: BLF 26C . $3.00
The adaptor connects the MC fluid outlet (furthest from the steering) wheel to the stock OEM hard brake line. Get the one from Autozone because its Brass and overall stronger than the equivalent adapter from O'reillys, which looked very maleable. The metal and precision of the small part looked inferior and weighed less. Not something I skimped out on when it comes to brakes.
The Results:
Wow! The pedal feels firmer than any truck ive ever driven. The stopping power is a night and day difference. I run 35/12.5/17in tires on my 2 door. I also had the mechanic install an extended rear SS brake line I bought 6 years ago (Skyjacker brand) and that might have helped helped too. My front lines are not SS. The rear SS was primarily so the line wouldn't break at full extension. Especially when on a mechanics lift, the rear stock rubber line was at maxxxxxx. You could touch it and it wouldn't move side to side due to all the tension. I'm lucky I didn't blow it before.
One thing to note. You can hear the rear drums squeak when you come to a stop from about 2mph to 0. I was told its just the increased pressure they are under and that it's okay. A bit annoying but not too loud like worn or warped front brake pads on a normal car.
I also replaced the front pads and rotors during my 4 month long Tahoe rebuild.