The 1968 AMC AMX is a compact two-seat muscle car built on a shortened Javelin platform. These cars are now 55+ years old, so most issues stem from age and deferred maintenance rather than inherent design flaws, though AMC's smaller dealer network meant parts quality was sometimes inconsistent.
Torque-Tube Rear Suspension Bushing Failure
Common · medium severitySymptoms: Clunking from rear on acceleration or deceleration, Rear axle windup feeling during hard launches, Vibration through driveline at highway speeds
Fix: AMC used a torque-tube setup where the driveshaft is enclosed. Rubber bushings at both ends dry-rot after decades. Requires dropping the entire tube assembly. 4-6 hours labor. OE-style bushings are NLA; most use polyurethane replacements.
Estimated cost: $400-800
Transmission Mount and Crossmember Cracking
Common · high severitySymptoms: Excessive driveline vibration especially with V8 torque, Transmission tail shaft dropping visibly, Clunking when engaging drive or reverse
Fix: The BorgWarner T-10 or T-96 transmissions common in these cars sit on a stamped crossmember that fatigues and cracks, especially behind 343/390 engines. Mount replacement is 2 hours, but if crossmember is cracked it needs welding or replacement—harder to source. 3-5 hours total.
Estimated cost: $350-900
Cylinder Head Cracking (290/343/390 V8)
Occasional · high severityTypical onset: 80,000-150,000 mi
Symptoms: External coolant seepage near exhaust ports, White smoke from exhaust on cold start, Overheating with no obvious external leaks, Coolant in oil (milky dipstick)
Fix: AMC V8 heads crack between valve seats and coolant passages, especially on 343s that ran hot. Requires head removal (8-10 hours per side), magnaflux inspection, and machining or replacement. Rebuildable cores are getting scarce. Often both sides need work once one is opened up.
Estimated cost: $2,500-4,500
Steering Box Worm Gear Wear
Common · medium severitySymptoms: Excessive play at center—two inches or more at rim, Wandering on highway requiring constant correction, Binding when turning lock-to-lock
Fix: Ross or Saginaw manual steering boxes wear internally. Adjustment helps temporarily but proper fix is rebuild or replacement. Rebuild kits available, 3-4 hours labor. Power steering cars (rare on '68 AMX) have fewer options—used cores are gold.
Estimated cost: $400-700
Fuel Sender and Tank Rust-Through
Common · medium severitySymptoms: Fuel gauge reading empty when tank is full or vice versa, Fuel odor in trunk area, Visible rust perforation on tank straps or bottom surface
Fix: Tanks rust from inside out, and senders corrode. Reproduction tanks now available (~$300-400 part). Requires trunk removal of spare tire well, disconnecting filler neck. 2-3 hours labor. Many owners retrofit modern sending units.
Estimated cost: $500-900
Front Lower Control Arm Bushing Deterioration
Common · medium severitySymptoms: Clunking over bumps from front suspension, Alignment won't hold—car pulls after fresh alignment, Uneven inside tire wear
Fix: Rubber bushings in the stamped lower A-arms turn to powder after 50+ years. Replacement requires pressing out old bushings, pressing in new. 3-4 hours labor both sides plus alignment. MOOG and Energy Suspension make replacements.
Estimated cost: $450-750
Main and Rod Bearing Wear (High-Mileage or Abused)
Occasional · high severityTypical onset: 100,000+ mi
Symptoms: Knocking from bottom end on cold start that quiets with oil pressure, Low oil pressure at idle when hot (under 10 psi), Metallic ticking that increases with RPM
Fix: AMC V8s are stout but decades of neglect show up in crank and rod journals. Bearing replacement requires engine pull (6-8 hours R&R), disassembly, possible crank grinding. Often leads to full rebuild if machine work needed. Budget includes labor for removal, bearing install, reassembly.
Estimated cost: $2,000-4,000
Buy one if you're handy and patient—parts scarcity and age-related issues mean this is a hobbyist car, not a reliable driver, but values are climbing and they're rewarding when sorted.
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.