1977 DODGE MONACO

Typical onset: original systems frequently fail by 60,000-80,000 mi, but many already bypassed

Symptoms: Intermittent stalling or no-start conditions, especially when hot, Surging or hesitation during cruise, Check engine light or poor fuel economy, Computer box mounted on air cleaner gets heat-soaked and quits

Fix: Most techs convert to traditional points or aftermarket electronic ignition (Pertronix, MSD). Lean Burn computer and pickup coil replacement runs 3-4 hours if you can find NOS parts, but conversion is 2 hours and far more reliable.

Estimated cost: $300-600

Typical onset: 80,000-130,000 mi

Symptoms: Rattling from front of engine on cold start that quiets after warmup, Erratic timing readings, won't stay in tune, Poor idle quality and hard starting when hot, Metal shavings in oil on drain

Fix: Replace timing chain, gears, and tensioner. On 318/360/400/440 engines this is straightforward—remove radiator, harmonic balancer, timing cover. Figure 4-5 hours labor for experienced tech. Always do water pump and front seal while you're in there.

Estimated cost: $450-800

Symptoms: ThermoQuad phenolic body warps and leaks fuel externally, Flooding, black smoke, or fuel smell in garage, Hesitation off idle or flat spots during acceleration, Choke pulls off too soon or not at all

Fix: ThermoQuads are notorious for warped bodies—most techs recommend replacement with Edelbrock 1406 or rebuilt Holley (2-3 hours). Rebuilding the original runs $300-400 in parts alone and often doesn't last. Holley 2280 is more rebuildable but still fussy with the feedback solenoids.

Estimated cost: $400-900

Typical onset: 70,000-110,000 mi

Symptoms: Clunking over bumps from front end, Wandering steering and vague center feel, Uneven tire wear on inside edges, Front end sags on one side

Fix: Lower control arm bushings rot out on these C-bodies. Requires press work or complete LCA replacement. Also inspect torsion bar sockets for cracks. Plan on 4-6 hours plus alignment. Upper ball joints usually need doing at same time.

Estimated cost: $600-1,200

Symptoms: Fuel gauge reads empty or erratic when tank has gas, Engine starves for fuel under acceleration or at quarter tank, Stalling after sitting—fuel drains back to tank, Rusty fuel smell from filler neck area

Fix: Drop the tank (2 hours), replace sending unit and pickup sock, clean interior if not too rusty. Tanks on these rot from inside out—if heavily pitted, replacement or coating required. Add fuel filter replacement in line.

Estimated cost: $350-700

Typical onset: 90,000+ mi

Symptoms: Delayed or no downshift when flooring throttle, Transmission stays in higher gear longer than it should, Mushy or vague transmission response, Linkage rod appears bent or loose at carburetor

Fix: The rod-and-spring kickdown linkage wears at pivot points and gets mis-adjusted. Replacement hardware kits available. Adjustment is finicky—1 hour for proper setup. Not adjusting it correctly causes premature trans wear.

Estimated cost: $150-300