1984 AMC EAGLE

Typical onset: 100,000-150,000 mi

Symptoms: Harsh or delayed 2-3 upshift, slipping in third gear, Burnt transmission fluid smell, dark red-brown fluid, No reverse or intermittent reverse engagement, Transmission cooler lines leaking at radiator connections

Fix: These Chrysler-derived automatics cook themselves when the cooler fails or fluid isn't changed every 30k. Rebuild requires 8-12 hours; many shops won't touch them anymore. Transmission oil cooler lines and radiator-mounted cooler typically need replacement simultaneously. External cooler addition is cheap insurance.

Estimated cost: $1,800-3,200

Symptoms: Transfer case won't engage 4WD or stuck in 4WD, HVAC only blows through defrost regardless of selector position, Hissing sounds under dash or from transfer case area, Rough idle that smooths when vacuum lines pinched off

Fix: The New Process 119 transfer case uses vacuum actuation that's prone to diaphragm failure and hardened hose collapse. HVAC system shares vacuum tree under hood. Diagnosis requires smoke machine or methodical line-by-line inspection. Plan 3-5 hours to replace all suspect lines, transfer case diaphragm, and check valves. Parts are NLA from AMC; use generic vacuum line and universal check valves.

Estimated cost: $300-600

Typical onset: 120,000-180,000 mi

Symptoms: Loud ticking/tapping from valve cover, cold or hot, Ticking that doesn't quiet down after 30 seconds of running, Loss of power, rough idle, occasional misfire, Metal shavings in oil, low oil pressure at idle when hot

Fix: The 258 uses flat-tappet hydraulic lifters that wear the cam lobes when oil changes are neglected or wrong oil is used (need ZDDP additives with modern oils). Requires valve cover removal to diagnose; full fix means cam replacement, all lifters, timing set while you're in there. 10-14 hours labor. Many techs won't do cam-only; they push for full rebuild due to age.

Estimated cost: $1,500-2,800

Typical onset: 80,000-130,000 mi

Symptoms: Gear oil dripping from rear wheel backing plates, Howling or rumbling from rear that increases with speed, Clunking when starting from stop, Visible gear oil coating inside of rear wheels

Fix: AMC 20 rear axle uses tapered bearings and axle seals that fail from age and contamination. Seal replacement alone is 2-3 hours per side but if bearings are notchy, you're pulling axle shafts for bearing/seal combo work. Drums often need machining. Budget 5-7 hours for both sides plus bearing/seal kits and possible brake hardware.

Estimated cost: $600-1,200

Symptoms: Hard starting when hot, floods easily, Black smoke from exhaust, fuel smell in cabin, Rough idle, stalling at stop signs, Visible fuel leaking from carb base or accelerator pump

Fix: The Carter BBD 2-barrel is simple but suffers from worn throttle shafts, bad float needles, and hardened gaskets. Most need full rebuild kits plus throttle shaft bushings by now. Rebuilds take 4-6 hours including removal, bench work, and tuning. Weber 32/36 swap is popular alternative (3-4 hours) and eliminates the problem permanently.

Estimated cost: $400-700

Symptoms: Bubbling paint along rocker panels below doors, Rust perforation at rear wheel arches above bumper, Liftgate bottom edge rotted out, water intrusion, Floor pan rust-through under rear seats (wagons)

Fix: Eagles rust from the inside out; rocker panels are double-walled and trap moisture. Surface rust is cosmetic; structural rot is common by now in salt states. Proper repair requires cutting out rockers, welding in patches or full replacement sections. Rear quarters often need patches. Budget 20-40 hours for quality metalwork depending on severity. This is the deal-breaker on most used examples.

Estimated cost: $3,000-8,000

Typical onset: 90,000-140,000 mi

Symptoms: Clicking or popping during tight turns, Vibration that increases with acceleration, Grease visible on inside of front wheels or frame, Clunking when shifting from Park to Drive

Fix: Eagles use a front driveshaft with dual CV joints (Spicer 1310 series) to accommodate suspension travel. Boot splits, grease escapes, joints wear. Replacement driveshafts are getting scarce; plan on rebuild with new CV joints and boots. 2-3 hours labor. Some shops replace entire driveshaft assembly if available.

Estimated cost: $400-800