IsItAGoodCar
Reliability Guide

Common Problems with the
1998–2003 BMW 5 Series (E39)

We've identified 5 known issues that can affect the 1998–2003 BMW 5 Series (E39). 3 of these are serious faults that could be expensive to repair.

5
Known Issues
3
Serious
1
Moderate
1
Minor

All Known Issues

Cooling System "Explosion"

SeriousCooling System

Plastic radiators, expansion tanks, and water pump impellers fail with age. One overheating event can warp the aluminium head or blow the head gasket on straight-six and V8 models.

Est. Repair Cost: £300–£600
Warning Signs:

Coolant smell after a run, Temperature needle rising past the center point, Steam or visible leaks from the front of the engine

What to Inspect:
  • Ask specifically for the age of the radiator and expansion tank
  • Check the fan clutch is engaging when hot
  • Inspect the plastic thermostat housing for cracks
Verified by IsItAGoodCar Research Team

ABS Module Failure (Bosch 5.7)

SeriousBrakes

On facelift models, the ABS module is located close to the exhaust manifold. Heat causes the internal wire bonds to fail, killing ABS and Traction Control.

Est. Repair Cost: £250–£600
Warning Signs:

ABS, DSC, and Brake warning lights all on (the "trifecta"), Speedometer and fuel consumption gauge stop working, Heavy steering if the car has Servotronic

What to Inspect:
  • Verify all warning lights extinguish after startup and stay off when hot
  • Check if the module has been relocated or shielded from heat
  • Read fault codes for "Wheel Speed Sensor" which often points to the module itself
Verified by IsItAGoodCar Research Team

V8 Timing Chain Guide Failure

SeriousEngine

On 540i models, the U-shaped plastic timing chain guide shatters, leading to potential engine destruction if the chain jumps.

Est. Repair Cost: £1,500–£2,500
Warning Signs:

Loud rattling noise from the front of the engine (sounds like a diesel), Plastic fragments found in the oil sump during a service

What to Inspect:
  • Listen for a "marbles in a tin can" sound on a warm idle
  • Drop the oil pan and check for brown plastic pieces
  • Ask for proof of chain, guides, and tensioner replacement
Verified by IsItAGoodCar Research Team

Thrust Arm Bush Failure (50mph Shimmy)

ModerateSuspension & Chassis

The front suspension relies on large rubber hydro-bushes in the thrust arms. When these leak or tear, the car develops a severe vibration through the steering wheel.

Est. Repair Cost: £150–£400
Warning Signs:

Steering wheel shake at 50–60mph, Judder through the steering when braking lightly from speed, Vague steering feel

What to Inspect:
  • Road test precisely at 50-60mph on a smooth road
  • Brake gently from 70mph and feel for steering vibration
  • Visually inspect the bushes for black fluid leaks (on original-style bushes)
Verified by IsItAGoodCar Research Team

Dashboard Pixel Loss

MinorInterior & Trim

The ribbon cables connecting the LCD screens to the instrument cluster and MID (radio) degrade, causing lines of pixels to disappear.

Est. Repair Cost: £100–£200
Warning Signs:

Illegible odometer or trip computer, Radio display missing text or numbers, Missing warnings in the check-control display

What to Inspect:
  • Check all displays in various lighting conditions
  • Run a cluster test (hidden menu) to see all pixels illuminated
  • Ask if a specialist repair (like AK Speedo) has been done
Verified by IsItAGoodCar Research Team

Buying Tips for 1998–2003 BMW 5 Series (E39)

  • ✓Inspect the jacking points, sills, and boot lid for severe rust, which is the main killer of UK E39s.
  • ✓Check the entire cooling system (radiator, water pump, expansion tank); the plastics become brittle and will suddenly shatter.
  • ✓Listen for knocking from the complex multi-link front suspension, indicating worn thrust arm bushes (the 'E39 shimmy' under braking).
  • ✓Ensure the instrument cluster pixels are fully readable, as they almost universally fade or drop out entirely.
  • ✓Check the M52/M54 straight-six engines for high oil consumption and leaks around the rocker cover gasket.
  • ✓Verify the ABS module functions correctly; warning lights (the 'trifecta' of ABS, Traction, and Brake lights) often mean a failed module.
1996–1997
Check a 1998–2003 BMW 5 Series (E39) by Registration