1978 AMC GREMLIN

Symptoms: Delayed or harsh shifts when hot, Burnt transmission fluid smell, Slipping between gears, Cooler lines leaking at crimps or radiator connections

Fix: Replace transmission oil cooler (often integrated into radiator or external), flush system, replace rubber lines that have deteriorated. Commonly requires radiator removal for integrated coolers. 3-5 hours labor depending on configuration.

Estimated cost: $400-900

Symptoms: Clunking when shifting into drive or reverse, Excessive driveline vibration, Visible sag of transmission tailshaft, Shifter feels loose or vague

Fix: Replace rubber transmission mount and inspect crossmember for rust-through. Original rubber has long since deteriorated on survivors. 1-1.5 hours labor, straightforward job.

Estimated cost: $150-300

Typical onset: 150,000+ mi or unknown maintenance history

Symptoms: Low oil pressure at idle when hot, Excessive blowby or blue smoke, Rod knock or main bearing rumble, High oil consumption (more than 1 qt per 500 miles)

Fix: The 258 I6 is exceptionally durable, but neglected oil changes or prolonged overheating lead to bearing and ring wear. Fix requires engine removal, full teardown, machine work, and reassembly. Most cost-effective to install a remanufactured short block or do complete overhaul with pistons, rings, bearings, and hone. 18-24 hours labor for R&R and rebuild.

Estimated cost: $3,500-6,000

Symptoms: Oil dripping from bellhousing area, Oil spots under car after sitting, Clutch contamination if manual transmission, Visible oil on flywheel or flexplate

Fix: Rope-style rear main seal hardens with age and leaks on nearly all survivors. Requires transmission removal and flywheel/flexplate off to access. Upgrading to modern two-piece seal is common. 6-8 hours labor with transmission R&R.

Estimated cost: $600-1,200

Symptoms: Hard starting after sitting, Stalling or stumbling under acceleration, Fuel smell in cabin or at rear, Visible rust particles in fuel filter

Fix: Original fuel tanks, lines, and filters have deteriorated after 45+ years. Inline fuel filter clogs frequently on aged survivors. Steel fuel lines rust through at mounting points and tank seams. Budget for complete fuel system inspection, filter replacement, and likely line and tank replacement or sealing. 4-8 hours depending on scope.

Estimated cost: $300-1,500

Symptoms: Rough idle or stalling, Black smoke or excessive fuel consumption, Hesitation on throttle tip-in, Flooding or fuel leaking from carb base

Fix: The Carter BBD two-barrel is simple but requires periodic rebuilding. Dried accelerator pump diaphragms, stuck float needles, and worn throttle shafts are typical. Full rebuild with kit and proper adjustment takes 2-3 hours. Many survivors benefit from professional carb rebuild or replacement with remanufactured unit.

Estimated cost: $250-500