1979 CADILLAC ELDORADO

Typical onset: 40,000-80,000 mi

Symptoms: White smoke from exhaust, Coolant loss with no external leaks, Hard starting when warm, Metal shavings in oil, Sudden loss of compression

Fix: The Oldsmobile 350 diesel suffers from inadequate head bolt design causing head gasket failures, plus weak main bearings and cracking blocks. Most require complete engine replacement or full rebuild with aftermarket ARP studs, hardened crank, and block inspection for cracks. 25-35 hours labor for R&R plus machine work.

Estimated cost: $4,500-8,500

Typical onset: 60,000-100,000 mi

Symptoms: Severe clunking when shifting into drive or reverse, Transmission appears to 'jump' under acceleration, Visible sag of transmission tail

Fix: The rubber transmission mount deteriorates and the THM325 droops, causing driveline vibration and harsh engagement. Requires transmission support and mount replacement. Often done with fluid service since trans must be partially lowered. 2-3 hours labor.

Estimated cost: $250-450

Typical onset: 70,000-120,000 mi

Symptoms: Transmission fluid leaking near radiator, Transmission overheating, Pink or red fluid in coolant overflow, Slipping gears after warmed up

Fix: Steel cooler lines rust through where they pass near the frame or at fittings. Worse, internal cooler failure allows coolant into transmission fluid, destroying clutches within days. Requires line replacement (1.5 hrs) or if coolant contamination occurred, full transmission flush or rebuild. 12-18 hours for rebuild.

Estimated cost: $200-400 for lines, $1,800-3,200 for contaminated transmission rebuild

Symptoms: Won't start after sitting months or years, Runs rough then dies, Fuel starvation under load, Black crusty deposits in carburetor

Fix: These cars sit unused frequently, and 1970s fuel systems corrode badly. Requires tank drop, cleaning or replacement, new fuel lines if rubber, carburetor rebuild (Rochester 4-barrel on gas), and fuel pump replacement on diesel. Gas models: 8-10 hours. Diesel with injection pump issues: add 6-8 hours.

Estimated cost: $800-1,800

Typical onset: 60,000-100,000 mi

Symptoms: Rough idle that worsens over time, Black smoke under acceleration, Won't start or extremely hard starting, Fuel in oil indicating pump seal failure

Fix: The Stanadyne DB2 injection pump leaks internally, loses timing, or seizes. Replacement pumps are scarce and expensive. Requires pump removal, core exchange or rebuild, and timing procedure. 6-8 hours labor if pump is available.

Estimated cost: $1,200-2,500

Typical onset: 80,000-130,000 mi

Symptoms: Clicking or popping when turning at low speed, Vibration during acceleration, Grease on inside of wheel, Clunking from front end

Fix: The E-body uses exposed CV joints that wear from age and torn boots. Front axle shafts need replacement as assemblies since boots alone rarely seal properly on 45-year-old parts. 3-4 hours per side including alignment check.

Estimated cost: $400-700 per side