Its Not You Its Me

[my67c20]

I know most are not computer nerds or have fully subscribed to application like Chat GPT or Co-Pilot, but occasionally I find these are good resources to initially understand the differences. Not that I subscribe to the world of useless customer service peeps, but......

Can you describe the differences between these part numbers from Inline tube? CTB71MC42 ,SCTB71MC44, CTB71MC44, SCTB71MC42

Copilot said:
Here’s a clear breakdown of what these four Inline Tube part numbers mean, based entirely on the information available in the official product listings and Inline Tube’s own explanation.

✅ Key Functional Differences
Inline Tube clarified the core difference:

MC44 kits = “Master Cylinder → Proportioning Valve” (master to valve)
MC42 kits = “Master Cylinder → Frame” (master to frame)
67-72chevytrucks
This means the 42‑series and 44‑series are not interchangeable because the routing and line shapes differ depending on whether the truck used a proportional valve setup or a direct‑to‑frame setup.

📦 Part-by-Part Breakdown
1. CTB71MC42 (OE Steel)
Material: OE steel
Function: Master cylinder to frame line kit
Vehicle Fit: 1971–72 Chevy/GMC truck 4WD ½ & ¾ ton
Notes: Designed to replace the short lines that run from the master cylinder toward the frame/ABS module.
inlinetube

2. SCTB71MC42 (Stainless Steel)
Material: Stainless steel
Function: Same geometry as CTB71MC42 → Master cylinder to frame
Notes: Although not listed directly in product pages, Inline Tube’s naming convention uses:
C = OE steel
SC = Stainless steel
Because MC42 = master‑to‑frame, the stainless version (SCTB71MC42) follows the same pattern.
(Functional relationship confirmed by Inline Tube’s explanation.)
67-72chevytrucks

3. CTB71MC44 (OE Steel)
Material: OE steel
Function: Master cylinder to valve (proportioning valve)
Vehicle Fit: 1971–72 Chevy/GMC truck 4WD ¾‑ton
Description: Preformed brake lines from the master cylinder to the valve/ABS module.
inlinetube

4. SCTB71MC44 (Stainless Steel)
Material: Stainless steel
Function: Master cylinder to valve
Vehicle Fit: 1971–72 Chevy/GMC truck 4WD ¾‑ton
This is the stainless counterpart to CTB71MC44.
inlinetube

🔍 Summary Table
Part Number Material Routing Type Meaning
CTB71MC42 OE Steel Master → Frame 42-series = frame routing
inlinetube
+1
SCTB71MC42 Stainless Steel Master → Frame Stainless version of MC42 kit
67-72chevytrucks
CTB71MC44 OE Steel Master → Proportioning Valve 44-series = valve routing
inlinetube
SCTB71MC44 Stainless Steel Master → Proportioning Valve Stainless version of MC44 kit
inlinetube