The 1998 Dodge Avenger shares the Mitsubishi-based JA platform with the Sebring coupe, combining decent handling with frustrating reliability issues. The 2.5L V6 (Mitsubishi 6G73) is the more common engine but brings significant head gasket and oil consumption problems, while the 2.0L four-cylinder is generally more durable but underpowered.
2.5L V6 Head Gasket Failure and Oil Consumption
Common · high severityTypical onset: 80,000-130,000 mi
Symptoms: White smoke from exhaust on startup, Coolant loss with no visible leaks, Milky oil on dipstick or oil cap, Excessive oil consumption (1 quart per 500-800 miles), Overheating under load
Fix: Both head gaskets fail due to poor design and inadequate coolant flow between cylinders 2-3 and 4-5. Requires removing both heads, resurfacing, new gaskets, timing belt replacement while you're in there, and often valve stem seals. Budget 14-18 labor hours. If oil consumption was severe before repair, expect piston ring damage requiring a full rebuild.
Estimated cost: $1,800-3,200
Automatic Transmission Oil Cooler Line Failure
Common · high severityTypical onset: 70,000-120,000 mi
Symptoms: Transmission fluid pooling under vehicle near radiator, Pink fluid mixing with coolant in overflow tank, Transmission slipping or delayed engagement after fluid loss, Overheating transmission warning
Fix: The steel cooler lines rust through where they attach to the radiator, and internal cooler can fail allowing cross-contamination. If coolant entered transmission, you're looking at a flush and often internal damage requiring rebuild. External line replacement is 2-3 hours; if contamination occurred, add transmission service or rebuild. Catch it early or you're buying a transmission.
Estimated cost: $200-400 (lines only) or $1,500-2,800 (with transmission damage)
Lower Ball Joint Separation (Recalled but Still Fails)
Occasional · high severityTypical onset: 60,000-110,000 mi
Symptoms: Clunking over bumps from front suspension, Steering wander or pulling to one side, Uneven tire wear on inside edges, Visible play when prying on wheel at 6 and 12 o'clock
Fix: Even after the 2004 recall for ball joint separation, these continue to fail prematurely. The ball joints are riveted into the control arms, so you're replacing entire lower control arms. Do both sides and get an alignment. 3-4 hours labor. Inspect these at every tire rotation—catastrophic failure means loss of steering control.
Estimated cost: $400-650
Crankshaft Position Sensor Failure (No-Start)
Common · medium severitySymptoms: Sudden no-start condition with cranking but no firing, Intermittent stalling while driving, Check engine light with P0320 or P0335 codes, Engine dies and won't restart until fully cooled
Fix: Heat-related failure of the crankshaft position sensor is extremely common and leaves you stranded. Sensor is located above the starter on the bellhousing. Relatively easy access on the 2.0L, more cramped on the 2.5L V6. Keep a spare in the glovebox. 0.8-1.5 hours labor.
Estimated cost: $150-280
Transmission Mounts Collapse
Common · medium severityTypical onset: 65,000-100,000 mi
Symptoms: Severe clunking when shifting from Park to Drive or Reverse, Vibration at idle in gear, Visible sagging of engine/transmission when viewed from below, Shifter vibration during acceleration
Fix: The hydraulic engine and transmission mounts fail regularly, allowing excessive powertrain movement. The front engine mount and rear transmission mount are the usual culprits. Replace all three mounts at once—they're all the same age. 2.5-3.5 hours labor. Use quality aftermarket or OEM; cheap mounts fail in 6 months.
Estimated cost: $350-550
Headlight Switch and Dimmer Relay Failure
Occasional · medium severitySymptoms: Headlights fail to turn on or work intermittently, Dashboard lights inoperative, Headlights stuck on high beam, Melted connector at back of headlight switch
Fix: The headlight switch overheats due to poor design and high current draw, eventually melting the connector. Multiple recalls didn't fully fix it. Replace the switch and repair or replace the melted harness connector. If ignored, can cause electrical fire. 1.5-2 hours labor including connector repair.
Estimated cost: $180-320
Fuel Pump Failure
Occasional · high severityTypical onset: 90,000-140,000 mi
Symptoms: Sudden loss of power while driving, No-start with no fuel pressure, Whining noise from rear seat area, Stalling after warm-up or at operating temperature
Fix: The in-tank fuel pump fails without warning, often related to running the tank low repeatedly. Replacement requires dropping the fuel tank. Always replace the fuel filter at the same time (often forgotten). 2.5-3.5 hours labor. Use a quality pump—cheap replacements fail quickly.
Estimated cost: $450-750
Hard pass unless you're getting it cheap and can wrench yourself—the 2.5L V6 head gasket failure alone makes this a money pit, and transmission cooler line failures compound the misery; a same-year Honda Accord is money better spent.
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.