sadpanda

I'm currently looking at getting a 2012 or 2013 ML350 (gasoline) for my wife, and I've come across a number of 2012s around or above the 100,000-mile mark. I've had good experiences with other high-mileage Mercs, so I'm trying to figure out what the sweet spot for price vs. mileage is. Obviously, I'd be looking out for maintenance records, provenance, but with some models that doesn't rule out many surprises.

When I searched MBWorld, I was surprised to find relatively few posts about high-mileage issues with W166s. The only consistent trouble seems to be with the Bluetecs. I'm hoping that, generally, the lack of posts equates to lack of common problems. Does anyone have any recommendation to stay away from a gasoline W166 with over 80k or 100k miles?

Also more specifically, has anyone had any bad experiences with maintaining the W166's Airmatic and Dynamic Curve? I've only come across one example with those two options. The dealer was transparent enough to send the inspection sheet with the issues it's currently got, including "front and rear level arms seized", "suspension sitting low in the front", cupped tires and "trans pan and rear main leaking". Even though it's sold at a heavy discount, I feel like this is a money pit just waiting to happen. Does anyone disagree?

Thanks in advance for all your thoughts.

easyedwin

I recently turned 82k on my 2012. Asside from warranty work [flex disks and oil and tranny gaskets] the only thing I have been required to pay for is the main battery [$400]. I had the extended elp warranty. It was worth every penny. I do not have airmatic, however.

OldMerc94

I'm at 110k with a 2013 ML550 w/ every option except Surround View Camera. Bought CPO w/ 3yr warranty. I love mine, but it's had a few challenges. Surprisingly, Air Springs haven't failed and not a single problem with the Active Curve System.

- Rear Tailgate Latch Failed, Replaced
- Fuel Injectors Leaked - replaced ECU, Wiring Harness, and Fuel Sensor (damaged by leaked fuel)
- Clacking Noise on Startup, Check Valve Replaced
- Right Rear Airmatic Damper Leaked, Replaced
- Clunk from Front on Turn, Right Half Axle Replaced
- Multi-Contour Seat Reservoir Exploded, Replaced
- Run Flat Tires Failed, Replaced w/ non-RFTs
- Battery Failed, Replaced
- Brake Pads / Rotors Front & Rear ($$)
- 3 windshields replaced (Arizona rocks)

Right now I still have a slight clunk on left turns which is likely coming from the other front half axle. Not sure if that's tied to 4matic or what.

If you pickup a RWD non-airmatic ML350 without ACS or Multi-Contour, there should be few problems if it's been properly maintained.

Find a highly optioned one and there may be a few issues to address. The most onerous repair was the leaking injectors which I think is unique to the M278 motor in a specific time span.

Given the choice, I'd make the same decision again. Key part being a warranty. ACS and airmatic give a fantastic highway ride. On/Off Road Package is surprisingly capable. Find what level of risk you're comfortable with and make a decision.

sgt1372

Just bought a 2012 ML350 4Matic w/98k miles on it for $22.5k.

Full service history and CarFax. Non Airmatic and non Dynamic Curve. Bought it "as is." No problems worth mentioning in the history. Runs great and everything works.

Had to put a new set of tires on it, repair some minor wheel rash on a couple of wheels and replace the windshield because it was severely pitted by road debris. Also added a full set of WeatherTech mats, MB valve stem caps, and new license plate frames and screw caps. Front passenger side mudflap was torn. Cut the dangling part off and cut off the driver's side front mudflap to match. The car looked good before but looks even better now.

Service was done every 10k miles. Brakes and rotors changed just 2 months ago and brake fluid flushed a year ago. Just need to get the 100k mile service done next week and that'll be it.

Very happy with the purchase.

sadpanda

Must be a Marine thing, because I just got home from picking up our 2012 ML350 4Matic w/98k miles from Kentucky! We drove almost 700 miles today, and so far this vehicle's been butter-smooth. It also needs its 100k A5 service shortly, but it's a 1-owner that was always dealer-maintained. Hopefully, my dealer will find the car to be in the same shape as the pre-purchase inspector did in KY.

I ended up staying away from Airmatic, btw. From this forum, I was under the impression that it was a common option, but my service advisor told me they never see any MLs with Airmatic (and there's a ton of MLs around here). He wasn't sure if it was a cost-effective option without a warranty.

Thanks for your feedback, guys!

chassis

How are the W166 folks doing? What are some latest mileage numbers? I have a GLE 350, while not an ML it's on the W166 chassis. I have 50k miles now, hoping to get 200k.

A 200k+ mile ML350 is listed for sale on Cargurus. Has anyone else achieved 200k?

Gibzki

My 2012 with 120K miles main issue was knock at start up. Check valve and replacing chain tensioner didn't fix the issue. Cam shaft adjuster is the next probable cause which shops are asking around 4K to fix it. I believe this issue was fixed with the 2014 models and up. Other than that, no other major issues here. Most comfortable ride I owned so far.

geniushanbiao

In terms of reliability it doesn't make too much difference between years.

I would suggest buying 2013+ instead of 2012 due to the NTG version. The 2012 uses NTG4.0 and 2013+ uses NTG4.5 or 4.7 which makes a pretty huge difference. I have a 2012 NTG4.0 and a 2015 GL350 NTG4.5/4.7 and I used to have a 2013 C300 with NTG4.5. Although functions are the same, the 4.5/4.7 respond much faster and have a better color tone (I feel). When I engage reverse, the 4.0 takes 1-2 seconds to switch while 4.5/4.7 switches immediately.

Isawelvis

Have ove 67,000 on 2015 ML 350 still have original brakes and battery. So far so good.

Steve Richo

I purchased a 2013 Bluetec with 75,000 Kms, I now have 120,000 Km. My first service was $7000 for split CV boot, split turbo boost line, and Adblue heater element failure. My sunroof has Alzheimer’s, if I open it it does not seem to remember how to close and lifts the rear to tilt, I have had it reset to closed but it needs a control unit which they tell me is expensive so am living without it. Just (2 weeks ago) had another service and it required another turbo boost line ($750) as I had an oil leak and the other side had split, rear damper needs replacing but advised to do in pairs $4400 in parts, I have ordered Aisin dampers for $1000, should be here in Nov. I also needed new rotors F and R $4000 from MB, I bought Zimmerman (sport package) rotors and Akebono pads, fitted the rears today hope to fit fronts tomorrow but am concerned about the AEB system isolation have not been able to find how to an isolation so the pistons are not pressurised but cost was $1650. I am in two minds about the value proposition of a vehicle of this calibre I have to say I love it, but will these cost continue or have I done most of the issues now? As a retiree in my case at least, funds are not endless. If I dump it I won’t get another quality vehicle for the money I get from it. Hope this helps.........

chassis

@Steve Richo The diesel OM642 engine will be problematic without end, unfortunately. As well as the emission related hardware connected to it.

It sounds like with the dampers and brakes you may have let them go awhile? Is that correct? Best practice is to stay on top of replaceable items such as those and the vehicle will provide reasonably long service.

Did/do you have water damage to the moonroof?

Steve Richo

Hi Chassis, I have followed the MB service schedule and always used the dealership to maintain the vehicle. The brakes are normal wear and tear I just was not prepared to pay the costs when I have the capability to do the job myself, my only concern is how to disable the AEB system for the front brakes in case the pistons are activated while I am replacing pads. After I purchased the vehicle I had initial repairs that I believe the owner knew about, my error was not having MB do a pre purchase inspection..... I was genuinely surprised on both turbo pipes splitting and indicates a weakness in design/materials in my opinion, the CV boot is again a wear and tear issue and could happen to anyone. Sunroof is a failure of the control module (weakness?) and is expensive so I choose to leave it closed. The adblue heater was a $4000 repair but after some discussion MB replaced at their cost maybe it is a known issue? This is my third MB and appears to have had more issues, maybe coincidence.

Kartergreg

Just wait until the oil cooler seals start leaking. You are just about ready for that with your mileage. Another nice bill to look forward to. I really liked the diesel until it started being a problem. Dumped mine just after the extended warranty expired.

NNNN

Are your turbo boost line those rubber hose feed air in the engine or they are the steel one from exhaust to the turbo? If they are the steel one, turbo blade may already damaged.
Mine turbo air charge hose after intercooler splited. It cost around $300 from ebay. Good thing is it is easy to change.

Stevee_

Currently at 91K on my 13' ML 550. It was sitting at 75k in March, but I've been taking my family out on little getaways a bit more this year. Car has been reliable and I do hope to get at least 150-200k miles out of the M278.

chassis

Just turned 60k miles a couple of days ago. So far so good. Some small oil leaks that don't seem to be getting worse. When the weather warms up I will give the vehicle a very close inspection.

I will schedule the 60k transmission oil change in a week or so. I will likely do the 60k engine oil change myself.

What mileages are people accumulating on their W166s?

C280 Sport

We only did about 4,000 miles this year on our ML. Total miles under 40,000 miles on the clock. No issues and nothing out of the ordinary for a SUV when it comes to maintenance. Stay clear of the BT and go gas.

histo12

Just came from dealership for Ignition coil replacement#3 and they recommended transmission oil front and rear differential oil change. My Mb 2015 ml350 (gas) got 46,160 on it . lost my schedule maintenance booklet Too early for trans and diff. change?

chassis

It's clear that dealers seek their own advantage. MB does not specify front axle, rear axle or transfer case oil change for W166, at least from 2016 onwards.

However, I believe in changing all fluids to achieve high mileage, regardless whether or not the manufacturer specifies it. 46k miles is early. Too early? It's up to you. I have 62k miles on my 2017 W166 and plan to change all of the drivetrain fluids this year. Mainly because I like to do it, but also to help with high mileage achievement (hopefully). I have never had a differential or transfer case problem with any vehicle I have owned. I have run several vehicles well beyond 200k miles. In the big picture, the differentials have very low risk for problems below 200k miles. The transfer case seems to have less design margin and therefore preventive maintenance seems prudent for it.

mikapen

89,000 miles on our W164 Bluetec (as I recall), 103,000 on our W166 Bluetec. Adblue heater at 65,000 miles - warranty.
Rear shocks and link bushings at 80,000 miles - warranty, brake PADS at 88,000 miles (rotors fine).
3rd gear accumulator at 1,500 miles - warranty.
I'm not sure where the "unreliability of diesels, comes from, other than @chassis continual badmouthing them.

My experienced with diesels is that many dealers don't order them for stock, and don't train the mechanics, or only one.
This has been my experience in all diesels I have owned from an '80 Isuzu P'uP (sweet little diesel) to Rabbit to Jetta to Toureg to Cayenne.
Since the technicians don't know them, you can get plenty of badmouthing, but very little substance. This used to be the case when fuel injection came along, then catalytic converters, then turbochargers.... you get the picture.

However, even though I haven't seen any real evidence of high diesel problems, there is always the increased probably that you dealer or shop may not be familiar with them, which could be problematic. Interview the dealer's technician.

chassis

Bluetec diesels are rubbish. It’s not me @mikapen it’s the product. I spent $9k out of my own pocket on my TDI Touareg, all diesel related. Turbo, EGR, DPF, nox sensors and more.

Bluetec is so bad that MB just settled a class action on the topic, and they no longer sell diesels in the US. Bad product, stay away.

mikapen

Did you see the settlement? It was nothing, just a slap in the face of the ambulance-chasing class action fake lawyers. And a recall to replace sensors and catalysts. Nice gesture, but not an bad engine. Or bad technology.
In fact the DEF, SCR and other modern diesel e-controls have been a boon to diesel longevity, and are far superior to the former EGR-heavy, engine-destroying "fixes."
With brand new exhaust parts and a new extended warranty, M-B diesels are quite attractive.
Unless you just don't like diesels - then stay away.

BlownV8

Please correct me if I'm wrong but the warranty does not cover oil cooler seals, timing chain failure, or spun bearings caused from recommended oil change intervals that are too long? Just covers the emissions related parts, right? Would have them fix the emissions issues, take the money, and sell for whatever I could get.

chassis

@mikapen What passenger car or SUV examples suggest DEF and SCR are boons to diesel longevity?

mikapen

Every manufacturer except the Dodge Boys, who were in denial as their EGR diesels shell out before 100,000 miles, from excessive EGR. They were the last to adopt modern emission controls for their engines. Now they have doubled their power because of DEF and related modern approaches.
So, roughly double the power and longer life. I like it.