Getting EDGEucated: The “75k Mile List”
E39 5 Series (1995-2003, including M) Edition
After years of working on BMW’s, we have begun to see common problems and maintenance concerns that need to be addressed on nearly every middle-aged BMW. E39 5-series cars, like all BMWs, have certain areas that need to be inspected regularly, and prospective owners should always have a pre-purchase inspection done to verify the condition of these items.
In this list, you will find items that should have been replaced or at least inspected by 75k-100k miles. Some are model specific, and will be noted as such.
Areas of Concern:
Thrust Arm Bushing Failure
The most common suspension problem on the E39. Common symptoms for torn or cracked thrust arm bushings are shimmy under braking at freeway speed. vague or rubbery feel in the steering, and excessive front tire wear. Extreme examples will also produce a clunking sound. EVERY 5 and 7 series car we have ever seen needs these replaced by 75k. Many need them by 40k!!
Tie Rod Wear
V8 Powered 5 series cars share many basic front steering components with the 7 series cars, including the recirculating-ball type steering gear and a tie rod end attached to each end of the center tie rod. The tie rod ball joints and idler arm bushing are prone to wear and any one of them may cause excessive tire wear and/or steering shimmy. If any of the ball joint boots is cracked (you’ll see grease coming out) then expect that component to need replacement eventually. All components should also be checked for excessive play, and replaced if necessary.
Worn and Loose Rear Ball Joints
The E39 5 Series shares rear suspension geometry with the E38 7 Series, including rear suspension components. The rear suspension joints are critical to maintain the alignment and stability of the vehicle. Worn compnents can cause unstable handling and excessive tire wear. As the E39 approaches 100K miles, expect the rear ball joints to wear out and need replacement.
Worn or Blown Shocks and Struts
Factory BMW shocks on the 5 series cars are very robust, frequently working adequately for over 100K miles. They do wear out though, and most folks who have been driving their cars since new hardly notice the deterioration as it is gradual. Symptoms include:Diving under braking and acceleration, excessive lean and suspension compression during cornering. Bouncy and uncomfortable ride. Shocks and struts may also visibly leak shock oil. On the E39 5-Series, EDGE generally recommends replacing the factory units with either new factory shocks or with Koni Sport shocks. When replacing shocks and struts at 100K or greater, the upper shock mounts, both fron and rear may also need replacement. This is a great time to install lowering springs or freshen up other areas of the suspension as well. You will be amazed at the difference a good set of shocks can make in both comfort and performance!
Worn or Failed Swaybar Endlinks
Worn swaybar endlinks can compromise handling. A worn swaybar can sound like a metallic clicking noise. There is no critical danger in a failed swaybar endlink, but the handling of the car is compromised.
Torn Subframe and Subframe Bushings
Especially prevalent on the E39 Touring. Torn or Worn subframe bushings may lead to subframe failure. Common symptoms of subframe failure are erratic handling and unidentified clunks, squeeks and bangs from the rear of the car. Early detection of a torn or cracked subframe bushing can prevent costly subframe repair and welding.
Ripped or Failed Guibo
A torn guibo (Flex Disc) will result in a perceivable ‘drivetrain elasticity.’ Acceleration will be preceded with a loud clunk as the guibo bolts bind together.
Water Pump Failure
Water pump failure is without a doubt the easiest way to cause extensive and expensive damage to your BMW. The main symptom will be a rapidly overheating motor. What occurs is that the bearing or impeller on the stock pump, breaks, completely disabling the cooling system. If you ever see the temperature gauge on your BMW climb above the 3/4 mark.
TURN THE CAR OFF IMMEDIATELY AND CALL A TOW TRUCK!!
We can’t stress this enough. Failure to catch the overheating motor in time can result in a warped head or even more severe engine damage. We recommend changing out the waterpump in six cylinder cars every 60-80k.
Cracked Radiator Necks
BMW loves their plastic radiator tanks….Unfortunately…The plastic around the radiator necks become brittle and crack with age, often without warning (see warning above.) Radiators should be thought of as 80-100k mile wear items. Trust us, this is cheap insurance!!
Thermostats and Housings
6cyl and e34 V8′s. The factory thermostat housing can eventually crack causing cooling system failure. Replacement with an aluminum housing, or replacing with the new composite units every 60k or so will prevent problems. We also recommend replacing the thermostat while the housing is off. Later e39′s have electronically controlled MAP cooling thermostats. These will eventually fail and will generally throw a check engine light. When this happens, the engine is running about 10 degrees hotter, and this hurts mileage and will eventually hurt the engine.
Fan Clutch Failure
Most fan clutches fail between 80 and 100k miles. They provide the primary cooling for your car, and are easy for us to diagnose.
Accessory Belt and Tensioner Failure
Worn tensioners and idler pullies will sound like a squealing noise from the engine bay. Belts should be inspected for cracks regularly. If a belt happens to snap, the cooling system will fail as the water pump will cease to operate. Power steering and the alternator will also fail to work. Again, pull over and shut the car off immediately should you suspect a belt failure or see the temperature gauge rise past the 3/4 mark.
Valve Cover Gasket
Prevalent on all BMWs, a burning oil smell could indicate a leaky valve cover gasket. If the condition continues unchecked, oil can seep into the spark plug holes and damage the ignition coils, resulting in costly replacement. Replacement of this inexpensive gasket is a good idea when changing sparkplugs as the coilpacks will already be out.
O2 Sensor Failure
Poor mileage, poor idle and flat spots in the power curve could be caused by bad O2 sensors. Even if your car isn’t throwing a check engine light, they may not be performing optimally. BMW recommends replacing the O2 sensors every 100k miles. Extended high-RPM running/racing and high-performance chips may shorten the replacement cycle.
96+ 6cyl cars only. If you have a poor idle and periodic Check Engine lights, you may have a bad oil seperator. This valve tends to go bad and introduce a vacuum leak which produces the above symptoms and will eventually strand you somewhere. We started seeing these a year ago and we are now repairing more and more cars with this problem. Typical mileage seems to be around 80k. The good news is that the part is only around $75..the bad news is that the labor runs about 4 hours, depending on the year of the car.
Clogged and Dirty Pollen Filter
If the flow of air out of the air conditioning and heater system is not as strong as it used to be, it strongly suggests the pollen microfilter of your car has become dirty and clogged over time. A damp and musky smell can also indicate a dirty filter. This is a service II replacement item.