The Strategy: 90% of squeaks are either dry guide rods or a pulley bolt that is too tight.
Dan1. Guide Rods (The Usual Suspect)
Symptom: Noise comes from the weight stack itself.
Fix: Even if you did it before, spray the chrome rods generously with silicone again. Then do 10 fast reps to coat the insides of the plates.
Dan2. The "Flick Test" (Pulleys)
Symptom: A rhythmic "chirp" or squeak from a black wheel.
Fix: Go to the noisy pulley. Loosen the bolt 1/4 turn. You must be able to flick the wheel and have it spin freely. If it doesn't spin, it's too tight.
Lisa3. The Cable Rub Check
Symptom: A scratching/scraping sound.
Fix: Look closely at the U-shaped metal guards around the pulleys. Is the cable touching the metal? If so, bend the guard away with a screwdriver.
Dan4. Main Pivot (Press Arm)
Symptom: A loud metallic groan when doing chest press.
Fix: The main axle bolt is crushed too tight. Loosen the large nut on the pivot arm by 1/2 turn to let the washers breathe.