Most common 2003 Mercedes-Benz ML500 problems
Share of the 13 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.
Mercedes-Benz ML500 complaints by model year
Best ML500 years: 2007, 2003. Years to avoid: 2006, 2002. Compare all years →
What 2003 Mercedes-Benz ML500 owners say
Engine & cooling
Loss of power steering driving on the freeway due to sudden break of idler arm pulley and subsequent shredding of belt. Problem is the pulley is made of plastic and cracked in two, leaving 1/2 the pulley and shredding the belt. This occurred at driving speed of 50 MPH and mileage around 169,650 on 2003 ML500. This was very dangerous. I was able to pull off the freeway as I was driving in the lane nearest freeway exits. Almost impossible but able to steer into a parking lot. Lucky it was 'rush' hour and traffic was slow on surface streets. Incredible safety issue due to difficulty to steer without power steering. Car is regularly maintained by german mechanic familiar with repair of mb engines in Germany.
Engine keeps getting over-heated even after a new engine fan has been replaced. However, after its replacement I took it to two Mercedes dealership to re-inspect and make adjustment to their installment of the fan but it keeps getting overheated. I also had a new water coolant tank installed but it is also leaking out the coolant and showing the warning light. These events happen after I top up the coolant tank and drive around 50 miles, then the overheating starts and the tank starts becoming empty.
Brakes
Tl* the contact owns a 2003 Mercedes Benz ML500. While driving approximately 40 MPH, the brake pedal was depressed and failed to respond intermittently. The ABS warning light illuminated. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was 81,000...updated 08/06/15 the consumer stated two lines from the reservoir to the hydraulic pressure regulator failed. Further investigation revealed all the brake lines had severe pitting and corrosion , as well as the fuel lines. Updated 08/13/15 updated 8/28/15 updated 09/01/15 updated 09/08/15 updated 10/01/15 updated 10/31/2017
Tl* the contact owns a 2003 Mercedes-Benz ML500. The contact stated that the ABS indicator kept randomly illuminating and the brake pedal traveled to the floorboard when it was depressed. The vehicle was taken to an independent mechanic, but was not diagnosed or repaired. The vehicle remained parked for over a year due to the risk of a potential crash. The dealer and manufacturer were not contacted. The failure mileage was not available.
Steering
Loss of power steering driving on the freeway due to sudden break of idler arm pulley and subsequent shredding of belt. Problem is the pulley is made of plastic and cracked in two, leaving 1/2 the pulley and shredding the belt. This occurred at driving speed of 50 MPH and mileage around 169,650 on 2003 ML500. This was very dangerous. I was able to pull off the freeway as I was driving in the lane nearest freeway exits. Almost impossible but able to steer into a parking lot. Lucky it was 'rush' hour and traffic was slow on surface streets. Incredible safety issue due to difficulty to steer without power steering. Car is regularly maintained by german mechanic familiar with repair of mb engines in Germany.
I paid my dealer for a repair of a component that was covered under a recall. How do I get a refund or credit for the expense. I have ml 500 Mercedes Benz 2003. My power steering pump failed and was replaced at the white plains n.y. Dealership.
2003 Mercedes-Benz ML500 engines & fuel economy
| Engine | Transmission | Drive | MPG city / hwy / combined |
|---|---|---|---|
| 5.0L 8-cyl | 5-speed automatic | 4WD/AWD | 13 / 16 / 14 |
EPA ratings. Class: SUV.
Frequently asked questions
Is the 2003 Mercedes-Benz ML500 a good car?
Based on 13 owner complaints filed with NHTSA, the 2003 ML500 rates better than average: 59% fewer complaints than a typical year of the ML500 at the same age. It is one of the best ML500 years by this measure. Complaint counts don't account for sales volume or individual maintenance, so have any used car inspected before buying.
What is the most common problem with the 2003 Mercedes-Benz ML500?
The engine & cooling — 5 complaints, 38% of all complaints for this model year. Next are the brakes (3) and steering (3).
How many recalls does the 2003 Mercedes-Benz ML500 have?
NHTSA lists no recalls for the 2003 Mercedes-Benz ML500. You can still confirm with your VIN using our VIN recall check.
What are the best and worst years of the Mercedes-Benz ML500?
The best years by complaints, compared at the same age, are 2007 and 2003. Years to avoid or approach with caution: 2006 and 2002. See the full Mercedes-Benz ML500 years comparison.
At what mileage do 2003 Mercedes-Benz ML500 problems happen?
The median mileage reported in complaints is about 111,000 miles; 0% of problems with a recorded mileage started before 50,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.