The 1972 Gremlin is a simple, basic economy car that suffers primarily from age-related issues rather than design flaws. The inline-six engines are near-bulletproof if maintained, but decades of deferred maintenance, rust, and worn transmissions plague survivors today.
Torque-Command Automatic Transmission Failure
Common · high severityTypical onset: 80,000-120,000 mi or any mileage with neglect
Symptoms: Slipping between gears, especially 1st-2nd shift, Delayed engagement into Drive or Reverse, Transmission overheating, burnt fluid smell, No cooler flow or collapsed cooler lines
Fix: The Torque-Command three-speed needs a rebuild or replacement. Cooler line and external cooler issues are epidemic on survivors—lines rot, coolers clog. Figure 8-12 hours for transmission R&R plus rebuild. Many shops won't touch these anymore, so finding a competent AMC transmission guy is half the battle.
Estimated cost: $1,800-3,200
Engine Rear Main Seal and Oil Pan Gasket Leaks
Common · medium severityTypical onset: Any—age and heat cycling are the main culprits
Symptoms: Oil puddles under bellhousing area, Oil coating transmission case and crossmember, Smoke from oil burning off exhaust components, Low oil level between changes
Fix: The AMC inline-six rear main seal is a two-piece rope or neoprene design that hardens with age. Oil pan gaskets cork out and leak. Rear main requires transmission removal—figure 6-8 hours labor. Oil pan is easier at 2-3 hours but crossmember often complicates access.
Estimated cost: $600-1,400
Worn Main and Rod Bearings (High-Mileage Engines)
Occasional · high severityTypical onset: 120,000+ mi, or earlier with oil neglect
Symptoms: Deep knocking sound at idle, worsens with throttle, Low oil pressure at idle (under 10 psi hot), Metallic debris in oil filter or pan, Sudden catastrophic failure if ignored
Fix: The 232 and 258 I6 engines are tough, but survivors often have unknown oil-change history. Bearing wear leads to low oil pressure and eventual rod knock. A proper rebuild with new bearings, honing, and fresh rings takes 18-24 hours for a competent tech. Many owners opt for a salvage long block swap at 12-16 hours instead.
Estimated cost: $2,500-4,800
Fuel System Varnish and Carburetor Issues
Common · medium severitySymptoms: Hard starting, especially when cold, Rough idle, stalling at stops, Flooding, fuel smell in cabin, Poor fuel mileage, black exhaust smoke
Fix: Decades of ethanol fuel and sitting wreak havoc. The Carter or Holley one-barrel carbs gum up, accelerator pumps fail, and needle valves stick. Tank often has rust and sediment. Plan on carburetor rebuild (2-3 hours) and new fuel filter, lines, and possibly tank cleaning or replacement (add 4-6 hours for tank).
Estimated cost: $400-1,200
Floor Pan and Torque Box Rust
Common · high severitySymptoms: Visible rust-through in driver/passenger floor, Soft or sagging floor when stepped on, Rear spring mounts and torque boxes crusty or gone, Water intrusion, musty smell
Fix: These are unibody cars with minimal corrosion protection from the factory. Floor pans rot from the inside out, and rear torque boxes (where leaf springs mount) can rust to nothing. Structural welding and patch panels are required—budget 12-20 hours depending on severity. Not a DIY job unless you can weld.
Estimated cost: $1,500-3,500
Worn Transmission and Engine Mounts
Common · low severityTypical onset: Any—rubber degrades with age
Symptoms: Excessive drivetrain movement during acceleration, Clunking when shifting into gear, Vibration at idle transferred into cabin, Transmission hitting crossmember or floor
Fix: Rubber mounts turn to stone or disintegrate after 50 years. Transmission mount replacement is straightforward—1.5 hours. Engine mounts (both sides) take 2-3 hours. These are wear items but often ignored until something contacts the body.
Estimated cost: $300-600
Buy one if it's solid and rust-free with service records; the drivetrain is robust, but hidden rust and deferred maintenance turn them into money pits fast.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.