2006 Mercedes-Benz ML350 Problems

What owners report

Owners of this model year most often describe internal engine wear that turns on the check engine light and blocks emissions inspection, along with transmission problems that can leave the vehicle in limp mode or without a working gear. Complaints also describe heated driver seats that scorched the upholstery, electrical faults linked to liquid reaching computers in the cargo area, and reduced power steering assist. Reports span a wide mileage range, with several engine and transmission problems appearing well under 100,000 miles.

1. 1
   Engine

   Balance shaft wear, check engine light, timing fault

   • 44 complaints (26%)
   • median 75,000 mi at 6.4 yrs old (35 state mileage)
   • owner-quoted repair $6,000 (median of 21 quotes)
   • filed 2009–2024

   Complaints describe the check engine light coming on and a diagnosis of worn balance shaft or timing gears inside the engine, with repair quotes commonly in the several-thousand-dollar range. Owners say the vehicle then fails emissions or registration inspection, and several report that the manufacturer offered little or no assistance. Some describe the engine running rough, losing power, or shutting down while driving. Mostly reported between roughly 45,000 and 135,000 miles, with several under 70,000 miles.

   2 related service bulletins

   What to check: Ask for service records showing whether the balance shaft and timing components have been replaced, and have a pre-purchase inspection read stored fault codes. A check engine light on this model should be diagnosed before purchase, since it can prevent passing an emissions test.

   2 excerpts from owner complaints in NHTSA records

   “2006 ML350 mercedes benz - balance shaft needs to be replaced in a car with under 50,00 miles on it. They want 8,000 to do the job and I am finding more and more people who are having the same issue with this car. I was directed to you by a facebook site that is for people who have the same issue with their mercedes. I think this is a flaw in the car and they should be recalled.”

   NHTSA complaint #10356196, filed 2010-09, 49,000 miles

   “2006 ML350 mercedes benz - check engine light has come on and the garage tells me that the balance shaft gears have worn and need to be replaced in a car with just 67,000 miles on it. The price is 5500 and there are many people I've heard from with the same issue with this car. I think this is an obvious flaw in this batch of engines and that there should be a recall as this is serious if the chains actually come off the gears.”

   NHTSA complaint #10373684, filed 2011-01, 67,000 miles
2. 2
   Transmission and drivetrain

   Transmission limp mode, harsh or missed shifts

   • 16 complaints (9%)
   • median 51,844 mi at 4.5 yrs old (14 state mileage)
   • 2 mention a crash, fire or injury
   • filed 2005–2023

   Owners describe the transmission dropping into limp mode, staying in a single gear, refusing to engage drive or reverse, or shifting harshly and jolting at low speed. Several say the dealer recommended a complete transmission replacement or work on the valve body and conductor plate, and some report the problem returned after control unit repairs. Reported from a few hundred miles up to about 100,000 miles, with many between 60,000 and 95,000 miles.

   5 related service bulletins

   What to check: Drive the vehicle from a stop through several upshifts and downshifts and watch for hesitation, harsh engagement or a limp-mode message. Ask whether the transmission control unit or conductor plate has been serviced, and check that no transmission fault codes are stored.

   2 excerpts from owner complaints in NHTSA records

   “When I drove my vehicle at low speed and came to stop, the vehicle jolted by moving forward. I believed this was caused by jerky transmission, and there was a bug in the software that controlled the transmission. I talked to a service guy at my dealership about this, and he told me that there was no fix at this time, awaiting an answer from mercedes benz.”

   NHTSA complaint #10151563, filed 2006-03, 2,100 miles

   “This vehicle has had nothing but problems. At around 32,000 it needed transmission repair. Unfortunately it was past the three year offered warranty. At around 45,000 miles, I was told that it needed new shocks. All of the repair men that I spoke with could not believe that this vehicle would need suspension work at such low mileage. After reading these posts, it is clearly a defect in the suspension. Meanwhile, I went through another set of tires because I am still waiting to repair the suspension. …”

   NHTSA complaint #10507346, filed 2013-04, 32,000 miles
3. 3
   Seats

   Driver seat heater overheating and burn holes

   • 13 complaints (8%)
   • median 80,000 mi at 7.1 yrs old (13 state mileage)
   • 10 mention a crash, fire or injury
   • filed 2010–2017

   Complaints describe the driver's seat heater producing a hot spot, a burning smell, and smoke within minutes of being switched on, leaving burn holes in the seat upholstery and in clothing. Owners say the dealer treated it as an out-of-warranty repair rather than an electrical fault. Reported from about 35,000 to 125,000 miles, typically within minutes of switching the heater on, often in cold weather.

   What to check: Inspect the driver's seat cushion and backrest for burn marks or repaired upholstery, and test the seat heater briefly while watching and smelling for overheating. Ask whether the seat heating element or control module has been replaced.

   2 excerpts from owner complaints in NHTSA records

   “I started the vehicle and as it was a cold morning I put my drivers seat heater on. Shortly after putting it on I felt a burning on the left side of my back, I pulled the car over and noticed a fire on the lower portion of the drivers seat(back wing). The fire burned through my jacket and burned my lower back.”

   NHTSA complaint #10482957, filed 2012-11, 124,125 miles

   “On jan. 6, 2017 northbound on hwy 52. Drivers seat heater had been on approximately 10 minutes when I felt a very hot spot on my upper left side. Then I smelled something burning. The seat heater had burned through the upholstery on the outboard bolster of the drivers seat and started burning through my coat.”

   NHTSA complaint #10945298, filed 2017-01, 80,000 miles
4. 4
   Electrical system

   Electrical faults from liquid reaching cargo-area control

   • 19 complaints (11%)
   • median 65,550 mi at 8.1 yrs old (17 state mileage)
   • 8 mention a crash, fire or injury
   • filed 2006–2023

   Complaints describe malfunction warnings, a rear liftgate that will not open, and in some cases smoke or fire after liquid spilled in the cargo area reached a control unit located there. Owners say the dealer identified the liquid damage as the cause and charged for computer and motor replacement, and some note there is no warning label in that area. Reported from very low mileage up to about 70,000 miles, often after a spill in the cargo area.

   3 related service bulletins

   What to check: Look for signs of past moisture or spill damage in the cargo-area trim and behind the side panels, and confirm the liftgate, tail lamps and interior electronics all work. Ask whether any control modules in that area have been replaced.

   2 excerpts from owner complaints in NHTSA records

   “When I was driving my mercedes benz ML350, the malfunction light came on regarding the rear lift gate. Shortly thereafter, I smelled smoke and took the car to the dealer. The dealer informed me that there was some kind of liquid spill in the cargo area. The liquid that spilled got into the central processing unit, causing an electrical short in the system and the rear lift gate would not open. The vehicle cpu caught fire due to the spill. …”

   NHTSA complaint #10253212, filed 2008-12, 52,051 miles

   “I have a 2006 me/be ML350 where the tail lights and stop lights don't work properly. This is a safety issue. The system goes into back up mode where another set of lights go on, this causes the computer to give false messages. The dealer wants over $300 for a rewiring kit and the manufacturer will not help. I feel the tail lights/stop light wiring should last the life of the car, which has not been in an accident or misused. A rewiring kit tells me this is a known problem. …”

   NHTSA complaint #10487349, filed 2012-12, 122,000 miles
5. 5
   Steering

   Reduced or lost power steering assist

   • 8 complaints (5%)
   • median 62,000 mi at 9.8 yrs old (6 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2008–2023

   Owners report the steering wheel becoming very stiff and hard to turn, sometimes without warning, often at parking speeds. Some say they were told their vehicle was not covered by a power steering recall, and others describe rattles or groaning noises from the steering when turning or over bumps. Mostly reported between about 50,000 and 80,000 miles.

   What to check: Check power steering fluid level and look for leaks or dampness at the cooling hose and clamp, and turn the wheel lock to lock at idle to listen for noise or feel for stiff spots. Ask whether the power steering hose clamp recall or any pump work was performed.

   2 excerpts from owner complaints in NHTSA records

   “Power steering fails, when turning into a parking space or parallels parking. This has happen for years and I was told that it can lock up . It was at one time a recall .and mercedes mention to me that the recall has ended. I dont have the money to fight this . But I have taking the car to mercedes to diagnostics and they wanted to charge me 100.00 . When I know this problem is part of the recall.”

   NHTSA complaint #11331689, filed 2020-06, 5 miles

   “In a parking lot, the power steering failed without warning. The steering wheel became difficult to turn. The vehicle had not been diagnosed or repaired. The manufacturer was notified of the steering malfunction. The approximate failure mileage was 65,000. Js”

   NHTSA complaint #10575843, filed 2014-03, 65,000 miles

Buying note. These vehicles can be solid when maintained, but the engine balance shaft and transmission repairs owners describe are costly, so a pre-purchase inspection with fault-code reading and service records matters more than mileage. Also verify whether the open brake booster recall (24V298000 or 22V315000) has been completed, and check the seat heater and cargo-area electronics during the test drive.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.