1979 BUICK CENTURY

Typical onset: 60,000-90,000 mi

Symptoms: slipping between gears especially 1-2 shift, delayed engagement when shifting to drive, whining noise under acceleration, transmission overheating

Fix: The TH200 3-speed automatic behind the 231 V6 is notoriously weak and fails early. Rebuild requires 8-12 hours labor but most shops recommend replacement with a used TH350 swap (requires custom crossmember work) or junkyard TH200 and pray. Transmission cooler lines and mounts typically need replacement simultaneously.

Estimated cost: $1,800-3,200

Typical onset: 50,000-80,000 mi

Symptoms: white smoke from exhaust, loss of compression, cracked cylinder heads, water in oil (milky dipstick), sudden loss of power, coolant consumption

Fix: The Oldsmobile 350 diesel is a nightmare—basically a converted gas engine with inadequate head bolts and weak block. Head gasket failure leads to coolant intrusion and rapid engine death. Rebuild requires 25-35 hours labor for short block minimum, but most need complete replacement. Parts availability is poor. Many owners convert to gas 350 V8 which requires different engine mounts, wiring, fuel system—figure 40-50 hours total.

Estimated cost: $4,500-8,000

Symptoms: hard starting when hot, rough idle that improves when warm, black smoke on acceleration, fuel smell in cabin, stalling at stop lights

Fix: The Rochester 2-barrel and 4-barrel carbs (depending on engine) develop worn throttle shafts, bad accelerator pumps, and stuck choke pulloffs. Full rebuild kit plus labor runs 3-4 hours. Ethanol fuel accelerates deterioration of rubber components. Computer-controlled carburetors on California models add electronic complexity that most shops can't properly diagnose.

Estimated cost: $400-750

Typical onset: 100,000-150,000 mi

Symptoms: deep knocking sound at idle, dropping oil pressure especially when hot, metallic rattling that worsens under load, oil light flickering

Fix: The Buick 231 V6 (3.8L) develops worn main bearings due to inadequate oiling and soft bearing material in this era. Requires complete engine removal and disassembly—20-28 hours labor for short block work including new bearings, crank inspection/possible machining, and reassembly. Crankshaft often needs turning which adds machine shop time and cost.

Estimated cost: $2,800-4,500

Symptoms: doors not closing properly, visible gaps between body and frame, clunking over bumps, sagging body corners, rust visible at rocker panels

Fix: Body mounts rot out completely in rust-belt cars, and the frame itself develops perforations behind front wheels and near rear spring mounts. Body mount replacement requires lifting body off frame (12-16 hours labor), but if frame is compromised the car is often totaled. This isn't a repair job—it's a parts-car situation once advanced.

Estimated cost: $1,500-3,000

Typical onset: 80,000-120,000 mi

Symptoms: clunking when shifting into gear, excessive vibration at idle in gear, visible transmission sag, harsh shifts

Fix: The rubber transmission mount deteriorates and the crossmember cracks from stress. Replacement requires supporting transmission, removing crossmember (2-3 hours labor). Often discovered during transmission service. Mount and crossmember together run $150-300 in parts plus labor.

Estimated cost: $350-600

Typical onset: 70,000-110,000 mi

Symptoms: spongy brake pedal, pedal sinking to floor, hissing sound when braking, brake fluid loss with no visible leaks, hard brake pedal requiring excessive force

Fix: Single-reservoir master cylinders on early '79s are dangerous—any leak loses all brakes. Dual-reservoir later models still fail internally. Vacuum booster diaphragms tear causing loss of assist. Master cylinder replacement is 2-3 hours, booster adds another 2-3 hours if needed simultaneously. Must be bench-bled properly and system fully bled.

Estimated cost: $450-900