1980 AMC SPIRIT

Typical onset: 80,000-130,000 mi

Symptoms: Slipping between gears especially 2nd-3rd, Delayed engagement when shifting to drive or reverse, Burnt transmission fluid smell and dark red/brown color, Loss of overdrive or stuck in second gear

Fix: Chrysler-sourced 904/998 automatics behind the 258 overheat and burn clutches. Transmission cooler lines rot out causing fluid loss. Full rebuild with updated clutches and bands takes 8-12 hours, external cooler addition recommended. Many shops quote replace vs rebuild due to parts availability.

Estimated cost: $1,800-3,200

Typical onset: 60,000-90,000 mi

Symptoms: Rod knock or deep knocking from crankcase, Metal shavings in oil on drain, Loss of oil pressure at idle, White smoke from excessive blowby

Fix: Pontiac-built 151 four-cylinder has weak crankshaft and rod bearings that fail prematurely. Piston ring wear causes oil consumption by 70k. Complete short block replacement or engine swap to 258 I6 is typical fix. Engine R&R plus rebuild/replace runs 16-24 hours labor.

Estimated cost: $2,500-4,800

Symptoms: Visible rust perforation at rear spring mounts, Clunking or shifting rear axle under acceleration, Sagging rear end or uneven ride height, Rear axle visibly off-center in wheelwells

Fix: AMC used minimal rust protection—rear crossmember and unibody spring perches rot from inside out, especially salt-belt cars. Requires cutting out affected metal and welding in patch panels or replacement crossmember. Fabrication plus alignment takes 12-20 hours depending on severity.

Estimated cost: $1,500-3,500

Typical onset: 50,000-100,000 mi

Symptoms: Hard starting when warm, floods easily, Black smoke and fuel smell from rich running, Hesitation or stumble off idle, Raw fuel leaking from carb base or accelerator pump

Fix: Carter BBD two-barrel and YFA single-barrel carbs suffer from worn throttle shafts, deteriorated floats, and vacuum leaks. Rebuilds rarely last—most techs swap to Weber 32/36 DGEV or Motorcraft 2150. Carb rebuild 2-3 hours, Weber swap 4-6 hours with tuning.

Estimated cost: $350-900

Typical onset: 70,000-120,000 mi

Symptoms: Oil pooling under bellhousing area, Oil drips from rear of engine onto exhaust, Low oil level requiring frequent top-offs (1 quart per 500-800 miles), Oil-soaked clutch if manual transmission

Fix: 258 I6 rear main rope seal hardens and leaks, pan gaskets seep from cork deterioration. Rear main requires transmission removal—8-10 hours labor. Oil pan on Spirit requires subframe drop or engine lift due to crossmember clearance, 4-6 hours. Often done together.

Estimated cost: $800-1,600

Symptoms: HVAC stuck on defrost or floor only, Check engine light (if equipped) and rough idle, Hissing sounds from under dash or engine bay, Poor fuel economy and high emissions

Fix: Miles of vacuum lines control everything from HVAC doors to EGR and distributor advance—all turn to dust after 40+ years. Systematic replacement of all vacuum lines with color-coded silicone takes 3-5 hours with diagram. CEC (Computerized Emission Control) components NLA—delete or bypass common.

Estimated cost: $200-500

Typical onset: 80,000-140,000 mi

Symptoms: Clunking over bumps from front suspension, Wandering steering and poor alignment retention, Excessive tire wear on inside edges, Visible torn rubber bushings at control arm pivots

Fix: Lower control arm bushings separate and allow excessive movement. Original rubber bushings are NLA—requires polyurethane upgrades or used-arm swaps. Press work plus alignment takes 4-6 hours both sides.

Estimated cost: $400-800