2004 LAND ROVER DISCOVERY

Typical onset: 80,000-150,000 mi

Symptoms: Coolant loss with no external leaks, white smoke from exhaust, Overheating, especially under load or when towing, Rough idle, misfires, loss of compression in one or more cylinders, Milky oil or coolant in oil—crossover happening internally

Fix: The 4.0L V8 uses pressed-in cylinder liners that can slip when overheated or improperly maintained. Once they move, coolant enters cylinders and oil galleries. Requires complete engine rebuild with properly sleeved block or short block replacement. Labor: 20-30 hours for full rebuild or swap.

Estimated cost: $4,500-8,000

Typical onset: 70,000-120,000 mi

Symptoms: Coolant consumption, overheating episodes, Exhaust gases in cooling system (bubbling in reservoir), White smoke on startup, loss of power, External coolant weeping between block and head

Fix: Often occurs alongside or before liner slippage. Both heads typically need resurfacing and new gaskets. Must address cooling system thoroughly—thermostat, radiator, water pump—or it will fail again. Labor: 12-16 hours for both sides.

Estimated cost: $2,500-4,000

Typical onset: 60,000-100,000 mi

Symptoms: Transmission fluid leaking from front of engine bay, Low trans fluid, slipping, delayed shifts, Transmission overheating warnings or limp mode

Fix: Steel lines corrode where they run along the frame and chassis. They can rupture suddenly, dumping all ATF in minutes. Replace with upgraded stainless or armored lines. Labor: 3-5 hours depending on rust and access.

Estimated cost: $400-800

Typical onset: 80,000-120,000 mi

Symptoms: Clunking on acceleration or deceleration, Excessive driveline vibration, especially in reverse, Visible sagging of engine/trans when inspecting from below

Fix: Rubber mounts deteriorate and allow excessive movement. Replace both engine mounts and the transmission mount together. Labor: 4-6 hours total for all three.

Estimated cost: $600-1,200

Symptoms: Hard starting, extended cranking especially when hot, Hesitation, stumbling under load, Stalling at idle after warm-up

Fix: In-tank pump strainer and inline filter clog from sediment, especially if prior owner neglected changes. Replace fuel filter (under driver's side, near tank) every 30k miles. If pump is failing, tank must be dropped. Labor: 1-2 hours for filter, 4-6 hours for pump.

Estimated cost: $150-300 filter, $800-1,400 pump

Typical onset: 60,000-100,000 mi

Symptoms: Overheating in traffic or under load, Coolant leaks from front of engine (water pump weep hole), Erratic temperature gauge, stuck-open or stuck-closed thermostat

Fix: Plastic radiator end tanks crack, water pump bearings fail, thermostats stick. Overheating accelerates liner slippage, so this is critical preventive maintenance. Replace radiator, water pump, thermostat, and hoses as a system. Labor: 5-8 hours.

Estimated cost: $800-1,500

Typical onset: 80,000-120,000 mi

Symptoms: Vehicle sagging on one corner or entire rear, Suspension fault warnings, compressor running constantly, Inability to raise or lower ride height

Fix: Air springs develop leaks, compressor wears out, or valve block fails. Many owners convert to coil springs ($600-1,000 all corners). Rebuilding air system: compressor 3-4 hours, air springs 2-3 hours each corner.

Estimated cost: $1,200-2,500 rebuild, $600-1,000 coil conversion