1966 CHEVROLET CHEVELLE

Typical onset: varies - age is bigger factor than miles

Symptoms: Slipping between gears, especially 1st to 2nd, Delayed engagement when shifting into drive, Transmission fluid burnt smell or dark color, Hard shifts or no movement in any gear

Fix: Full rebuild with clutch packs, bands, seals, and filter. Powerglide is simpler (8-12 hours), TH350 runs 10-14 hours. Original Powerglides often have worn direct clutch drums. Include new torque converter and external cooler during rebuild.

Estimated cost: $1,800-3,200

Typical onset: 80,000-150,000 mi or unknown history

Symptoms: Deep knocking sound at idle that worsens with RPM, Low oil pressure especially when hot, Metallic shavings in oil or filter, Sudden catastrophic failure if ignored

Fix: Requires engine removal and full teardown. Replace main bearings, rod bearings, often need crankshaft machining. If cylinders are scored, becomes full rebuild with pistons and rings (add 8-10 hours). Plan 25-35 hours for complete in-frame overhaul, 18-22 for just bottom end if lucky.

Estimated cost: $3,500-6,500

Typical onset: 100,000+ mi or decades of short trips

Symptoms: Blue smoke on startup or deceleration, Excessive oil consumption - quart every 500-800 miles, Poor compression readings across multiple cylinders, Blowby visible at oil filler cap

Fix: Engine must come out for proper ring job. Cylinders need honing or boring if tapered, pistons may need replacement if ring lands are damaged. Figure 30-40 hours for proper rebuild including new cam and lifters while it's apart. Shortcuts fail quickly.

Estimated cost: $4,000-7,000

Symptoms: Hard starting after sitting, runs fine once warm, Stumbling or dying at idle, Rust particles in fuel filter, Carburetor flooding or sticking

Fix: Tank often rusted through from ethanol fuel and age. Drop tank, inspect or replace (3-5 hours). Fuel lines need inspection - many still have original steel that's internally corroded. Carburetor rebuild adds 4-6 hours if Rochester or Holley is gummed up. Budget new fuel pump too.

Estimated cost: $800-1,800

Symptoms: Clunk when shifting from park to drive, Excessive vibration through floor at idle, Visible sagging or cracking of rubber mount, Driveline angle off causing u-joint wear

Fix: Original rubber mounts disintegrate after decades. Simple replacement, but requires supporting transmission with jack. 1.5-2.5 hours including crossmember removal. Do both engine mounts at same time if they're original.

Estimated cost: $200-400

Symptoms: Catastrophic knocking followed by engine seizure, Spinning rod bearing evidence in oil pan, Crankshaft journals scored or out-of-round beyond machining limits, Usually follows ignored low oil pressure warnings

Fix: Total disaster requiring crankshaft replacement or exchange. Engine R&R, complete disassembly, new or reground crank, line boring of block sometimes needed. 35-50 hours depending on machine shop work required. Often cheaper to source running used engine.

Estimated cost: $5,000-9,000