The 1998 Discovery with the 4.0L V8 (Rover engine) is a capable but maintenance-intensive truck known for cylinder liner slippage that can destroy the block, plus chronic overheating, head gasket failures, and cooling system weaknesses that cascade into catastrophic engine damage if ignored.
Slipped Cylinder Liners (Engine Block Failure)
Common · high severityTypical onset: 80,000-150,000 mi
Symptoms: Coolant loss with no visible external leaks, White smoke from exhaust on startup, Overheating that progressively worsens, Rough idle or misfires that develop suddenly, Milky oil or coolant in oil pan
Fix: The Rover V8 uses pressed-in cylinder liners that can slip when overheated, allowing coolant into the cylinders. Only real fix is a short block replacement or full engine rebuild with proper liner installation. 18-24 labor hours for R&R and rebuild/replacement. Many owners opt for used engines or top-hat liner kits during rebuild.
Estimated cost: $4,500-8,000
Head Gasket Failure (Both Banks)
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: Coolant disappearing without visible leaks, Overheating under load or in traffic, White exhaust smoke, Bubbling in coolant reservoir when running, Loss of power and rough running
Fix: The 4.0L V8 head gaskets fail frequently, often from cooling system neglect or overheating. Requires both heads pulled, decked if warped, new gaskets, and all cooling system components replaced while you're in there. 14-18 labor hours. If heads are cracked (common), add machine work or replacement heads.
Estimated cost: $3,200-5,500
Cooling System Cascading Failures
Common · high severityTypical onset: 70,000-130,000 mi
Symptoms: Overheating gauge creeping up in traffic, Coolant leaks from hoses, radiator, or water pump, Heater blowing cold intermittently, Steam from under hood, Reservoir pressure cap failing
Fix: Plastic radiator end tanks crack, hoses become brittle, water pump fails, and thermostat housings leak. The system is marginal from the factory. Best practice: replace radiator, water pump, thermostat, all hoses, and expansion tank as a package. 6-8 labor hours for comprehensive overhaul. Skimping on this WILL lead to liner slippage or head gasket failure.
Estimated cost: $1,800-2,800
Transmission Oil Cooler Line Leaks
Common · medium severityTypical onset: 80,000-140,000 mi
Symptoms: Transmission fluid puddles under front of vehicle, Burnt transmission fluid smell, Erratic shifting or slipping when fluid gets low, Fluid mixing with coolant if internal cooler fails
Fix: The transmission cooler lines and radiator-mounted cooler corrode and fail. External lines can be replaced with braided stainless upgrades. If the internal cooler in the radiator fails, coolant and ATF mix—requiring transmission flush, radiator replacement, and often transmission rebuild. External line replacement: 2-3 hours. Internal cooler failure adds radiator R&R and trans service.
Estimated cost: $400-800 (lines only), $2,500-4,000 (if internal cooler contaminates trans)
Driveshaft Center Support Bearing Failure
Occasional · medium severityTypical onset: 90,000-150,000 mi
Symptoms: Clunking or vibration on acceleration, Grinding noise from underneath at highway speed, Vibration that worsens with load, Visible wobble in driveshaft when spinning on lift
Fix: The two-piece driveshaft center carrier bearing wears out, especially if u-joints aren't greased. Replace the carrier bearing and inspect/replace u-joints at the same time. 2-3 labor hours. NHTSA had a recall for driveshaft issues, so verify if already addressed.
Estimated cost: $500-900
Transfer Case Viscous Coupling Seizure
Occasional · medium severityTypical onset: 100,000-160,000 mi
Symptoms: Binding or shuddering in tight turns, Transmission feels like it's fighting itself, Increased fuel consumption, Whining noise from transfer case area, Tire scrubbing on pavement when turning
Fix: The viscous coupling unit (VCU) in the transfer case can seize, locking the center diff and causing driveline binding. Requires transfer case removal and VCU replacement or rebuild. 6-8 labor hours. Some shops recommend switching to aftermarket lockable center diffs.
Estimated cost: $1,500-2,500
Air Suspension Compressor and Bag Failures
Common · low severityTypical onset: 70,000-120,000 mi
Symptoms: Vehicle sagging at one corner or entirely, Compressor running constantly, Warning lights on dash (suspension fault), Harsh ride quality, Compressor overheating and shutting down
Fix: Air springs crack and leak, compressor overworks and fails. Many owners convert to coil springs (EAS delete kit) to eliminate the headache. Air bag replacement: 2-3 hours per corner. Compressor: 3-4 hours. Coil conversion: 6-8 hours but permanent fix.
Estimated cost: $800-1,200 per air spring, $1,200-1,800 compressor, $1,500-2,200 coil conversion
Only buy if you're mechanically inclined, have a $5k emergency fund for engine work, and understand you're adopting a high-maintenance classic—otherwise walk away.
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.