The transmission solenoid failed; which caused transmission shift problems. I replaced the part (part # 8634960)
The dash gauge cluster lights too dim.
Center console lid hinge breaks easily.
Poor seal on T-Tops causing wind noise & possible leaks.
Valve seals often fail around 60,000 miles.
The 1983 through 1988 Monte Carlos are very special cars. My 1988 SS came from the factory with Camaro Heads, L81 Corvette Cam, Aluminum Intake Manifold, 750 cfm Q-Jet 4 barrel carburetor, Z-28 Fuel Pump, F41 Sport Suspension, 3.73 Posi. rear gear. The engine is a L69 with Valve size 1.84/1.50, flat top pistons & 9:5:1 compression. Only 16,204 SS were produced in 1988; actually produced in 1987. My garage will always have a Monte Carlo SS.
The Heads on the 1983-1988 Monte Carlo SS are from the CFI (Cross-Fire Injection) Camaro's. The where a real hamper on performance, but reduced emissions greatly because of there inability to flow lots of air. Good luck with your SS.