1971 CADILLAC FLEETWOOD SIXTY SPECIAL

Symptoms: Pink milkshake appearance in radiator or transmission fluid, Transmission slipping or delayed engagement after coolant intrusion, Engine overheating if transmission fluid enters cooling system, Sudden transmission failure if contamination goes unnoticed

Fix: Replace transmission cooler (often integrated into radiator), flush both cooling system and transmission completely, replace transmission fluid and filter. If contamination sat for any time, expect internal transmission damage requiring rebuild. 6-10 hours labor for cooler and flush; add 18-25 hours if transmission needs rebuild.

Estimated cost: $800-1,200 for cooler/flush only; $3,500-5,500 if transmission rebuild required

Symptoms: Hard starting after sitting, especially when cold, Rough idle, hesitation, or stalling, Black smoke from tailpipe indicating rich condition, Fuel leaks from carburetor gaskets that have hardened

Fix: Rochester Quadrajet needs complete disassembly, ultrasonic cleaning, new gaskets and accelerator pump. Replace fuel filter, inspect fuel lines for cracking. Ethanol fuel accelerates this issue. 4-6 hours for proper carburetor rebuild and fuel system service.

Estimated cost: $650-1,100

Typical onset: 60,000-90,000 mi

Symptoms: Clunk when shifting from park to drive or reverse, Vibration through floorboards at idle in gear, Visible transmission sag when inspected on lift, Driveline vibration at highway speeds

Fix: Replace transmission mount and inspect engine mounts while accessible. Original rubber deteriorates after 50+ years regardless of mileage. 2-3 hours labor, straightforward job.

Estimated cost: $350-550

Typical onset: 120,000-180,000 mi

Symptoms: Low oil pressure at idle when hot (under 10 psi), Knocking or rumbling from lower engine block, Metal particles in oil during changes, Pressure improves with RPM but drops dangerously at idle

Fix: Requires engine removal, crankshaft inspection/grinding, main bearing replacement. These engines have soft bearing material that wears if oil changes were neglected. Often find crank needs 0.010" or 0.020" undersize bearings. 25-35 hours for proper engine R&R and bearing replacement; add machine shop time for crank work.

Estimated cost: $4,500-7,000

Typical onset: 100,000-150,000 mi

Symptoms: Blue smoke on startup and during acceleration, Burning 1+ quart of oil every 500-800 miles, Poor compression test results (under 120 psi), Crankcase pressure pushing oil past valve covers

Fix: Rings wear due to cylinder wash from overly-rich carburetion or carbon buildup. Proper fix requires honing cylinders and new rings; often find ridge at top of bore. If cylinders are scored, needs full rebuild or short block. 30-40 hours for complete ring job with engine R&R and cylinder work.

Estimated cost: $5,000-7,500

Symptoms: Climate control defaults to defrost position, Cruise control inoperative or surges, Headlight doors operate erratically, Hissing sounds from under dash

Fix: All vacuum lines turn to dust after 50+ years. Requires systematic replacement of rubber vacuum hoses throughout engine bay and dash. Check vacuum reservoirs for leaks. 3-5 hours to do properly with diagram in hand.

Estimated cost: $400-700