Based on our shop experience specializing in heavy-duty brakes since 1985:

• Pushrod Alignment: When installing firewall-mounted booster brackets, ensure your structural linkage aligns squarely with the manual pedal arm block. Even minor offset tracking friction creates premature pushrod wear or internal bore score leaks over time.
• Check Valve Integrity: Always inspect your vacuum supply grommet and check valve assembly when mounting replacement canisters. Sluggish or hard pedal response is frequently traced to cracking intake check components rather than internal diaphragm leaks.
• Master Pin Depth: Verify the front output pushrod rod pin depth setting match closely against your legacy master cylinder piston dimple block prior to closing lines.