1972 CADILLAC CALAIS

Typical onset: 80,000-140,000 mi

Symptoms: Pink or milky transmission fluid, Overheating transmission, Coolant in trans pan during service, Sluggish shifts or slipping, Strawberry milkshake appearance in radiator

Fix: Factory cooler is integrated into the radiator's bottom tank. Leak allows coolant and ATF to mix, destroying both systems. Requires radiator removal, new or re-cored radiator with new cooler section, complete trans flush or rebuild if contamination reached clutches (common). External auxiliary cooler highly recommended. 6-10 hours labor depending on trans condition.

Estimated cost: $800-3,200

Typical onset: 100,000-150,000 mi

Symptoms: Deep knocking at idle when hot, Oil pressure drop below 10 psi at idle, Metallic rattling on cold start that worsens, Metal shavings in oil filter

Fix: The 472/500 Cadillac engines have marginal oiling to rear main bearings, worsened by sludge buildup or worn oil pump. Once bearings fail, engine rebuild or replacement required. Expect crankshaft machining or replacement, full bearing set, freeze plugs, timing set, gaskets. 20-28 hours for in-frame rebuild; add 8-12 hours for R&R if short block swap.

Estimated cost: $3,500-6,800

Typical onset: 60,000-100,000 mi

Symptoms: Clunk when shifting from Park to Drive, Vibration at highway speeds, Visible sagging of transmission tailshaft, Exhaust rattle against floor tunnel

Fix: The heavy TH400 and 472's torque destroy the rubber transmission mount, which is crossmember-mounted. Failed mount allows driveline angle to change, causing U-joint wear and floor pan contact. Replace mount and inspect driveshaft for imbalance. 1.5-2.5 hours labor.

Estimated cost: $180-380

Typical onset: 90,000-130,000 mi

Symptoms: Blue smoke on deceleration or startup, Oil consumption exceeding 1 quart per 500 miles, Fouled spark plugs on specific cylinders, Loss of compression on leak-down test

Fix: Early emissions tuning ran these engines rich and hot, causing ring land carbon buildup and stuck rings. Requires cylinder head removal, honing, new rings, possibly pistons if ring lands are damaged. If cylinders are scored, full bore and oversize pistons needed. 16-22 hours labor.

Estimated cost: $2,200-4,800

Symptoms: Hard starting after sitting, Stumble or hesitation under load, Stalling at idle, Difficulty reaching operating temperature

Fix: Modern ethanol fuel dissolves 50-year-old tank varnish and deteriorated rubber fuel lines. Inline filter clogs rapidly. Tank should be dropped, cleaned or replaced; all rubber fuel hoses replaced with ethanol-compatible; mechanical fuel pump diaphragm checked. Carburetor may need rebuild if varnish reached it. 4-8 hours depending on tank condition.

Estimated cost: $450-1,400

Typical onset: 100,000-140,000 mi

Symptoms: Delayed engagement into Reverse, Slipping on 2-3 upshift under load, No engine braking in Low range, Burnt ATF smell

Fix: The TH400 behind the 472 handles torque well but intermediate band adjusters seize, and clutch packs wear from heat. If caught early, band adjustment and fluid service may extend life. Once slipping occurs, full rebuild with clutches, bands, seals, and filter required. 8-12 hours for remove, rebuild, reinstall.

Estimated cost: $1,800-3,200