Considering a 2007 ML320 CDI, known problems ? advice ? - PeachParts Mercedes-Benz Forum

GregMN · #1 02-12-2014, 11:48 AM

I have been shopping for a 2005/2006 E320 CDI.
But I have been distracted by the siren song of the 2007 ML320 CDI with it's AWD. We live in northern MN.
I have read horror stories about expensive ($7000) catastrophic transmission failures.

What insight can forum members give me on this issue. I am only looking at 2007 ML320 CDI's.
So if the problems were from different years, or only occurred with an engine other than the 320 CDI, that would be good information to know.
If the problems were from abuse or lack of maintenance, I can deal with that. If it is random, I do not want to trust luck and may stick to the E-class.

I will cross post this in ML section of the forum too.

Thanks,
Greg

65aircooled · #2 02-12-2014, 12:46 PM

No ML advise here, but I can tell you about my love affair with my recently acquired E320 CDI

.

jay_bob · #3 02-12-2014, 07:57 PM

We have had a 2008 ML320 CDI since July. This is essentially the same vehicle as a 2007, and I would recommend you consider 2008s as well, since they do not use AdBlue either (that started in 2009 for the ML320s).

The car we purchased came from our local MB dealer in town. This was a local car, as verified by carfax and the prior owner's info on the VMI copy the dealer showed me. (He let me keep a copy for my records after redacting the PO's info.) The car had been meticulously maintained at the dealer every 10 k per schedule and had very few issues while it was on warranty. It had 106k on it when we bought it and we are now up to 113k.

I think the PO decided to trade it in when the catalytic filter got plugged, and I think the owner did not want to spend 3k to get it replaced at the dealer. The dealer replaced it before putting it up for sale. If you are looking at a model with near 100k miles, I would check to see if that cat has been replaced.

The good:
It feels like it will power through anything. We call it "the beast".
Great highway cruiser, returns mid 20s MPG on Diesel. Gas powered models take premium unleaded (which is within a few cents of Diesel here) and return mid-high teens.
Interior well put together but you can definitely tell the bean counters got after the engineers for cost reductions.
Does not require AdBlue, so you do get a spare. Unfortunately it is a compact spare.
Has plenty of room in the second row as long as the front seat passengers do not have the seats all the way back. I am 6"3' and have plenty of headroom and the seat is only back about 90% of the way.

The warts:
Audio system sounds great, and has near competition levels of bass available, but the Bluetooth and iPod integration is just not up to today's standards. It works but it is not as slick as the modern units. No A2DP support (to be fair, that wasn't released in the mid 2000s when these cars were designed). The navi works but again it's clunky compared to modern units. Negotiate with the dealer for a new navi DVD, they are several hundred dollars.
Power tailgate can be cranky. Sometimes it goes up by itself, sometimes not. I think the system is getting weak because if I give it a helping hand on opening, it will finish by itself. It is very complex and uses a hydraulic pump buried beneath the floor board to operate a cylinder in the roof.
Tires: The stock tires are 19" ($$$$) and you can count on having to replace the TPMS sensors. I had to replace the tires, a set of Contis were $995 out the door, and I bought the TPMSs online for another $260, and gave them to the tire guy to put in while he had the rims open.
Maintenance: The dealer will kill you with oil changes. DIY is not too bad especially with a topsider. However you must use only "Mobil1 ESP Formula M 5W40" and it takes 9 quarts at ~$12/quart. Oil every 10k, fuel filter every 20k.
Trans fluid: Manual calls for one time at 40k then you are "good for life", well we know what that means if you have a W210 or later with the 722.6 transmission. I would recommend fluid changes at least every 50k after that. It takes a special MB fluid that is mandatory for this transmission and it too is in the teens of dollars/quart. It takes 9 quarts and the procedure is complex as there is no dipstick to check the fluid level.
Systems complexity: If you are used to an IDI engine (aka OM61x or OM60x) you will be in for a huge surprise. The OM642 looks like the space shuttle main engine in comparison. Others on the forum call it the "rubber band ball".
Fuel cleanliness: Because it is a CDI, water or contaminants in the fuel are fatal to the injectors. For this reason you have to be picky about where you buy fuel. The fuel filter does have a water separator built in.

Even with all that I would recommend purchasing one that has been well maintained and has complete service records.

jay_bob · #4 02-12-2014, 08:20 PM

And another thing, after seeing your signature. I may be wrong but I do not think CDIs will tolerate WVO or high biodiesel concentrations.

Skid Row Joe · #5 02-12-2014, 09:24 PM

My take on the ML Class is that they will be costly vehicles to own and drive any amount of mileage.

The 05/06 CDI E320s have their own weak points, but I've yet to experience any transmission troubles with any MB diesel car I've owned or had in our family. Of course luck, care and maintenance may have had something to do with it, but all of our cars were either bought new, or had been in the highly desirable category of very well kept, somewhat new when we bought them.

Transmissions don't even register on my worry-index with their solid 45 years and running reputation with me.

If you're looking to save money on an ML for your transportation needs in an AWD, frankly, unless you're willing to spend a lot of money on it, I would go to another brand.

The E320 CDIs will cost you money to keep on the road too, there's no question about that either, but they're not to be compared to the higher cost(s) related to the ML series to do the same.

I would go over whatever I bought with a fine tooth comb before buying as to it's history/care/and condition.

GregMN · #6 02-12-2014, 10:40 PM

Bob & Joe,

Thank you for your input. Decisions, decisions, decisions....

Greg

Skid Row Joe · #7 02-13-2014, 01:57 AM

Quote:

Originally Posted by GregMN

Bob & Joe,

Thank you for your input. Decisions, decisions, decisions....

Greg

On reflecting......here's something that I believe I would do. Rather than buy the astronomical price of a near-new ML CDI, how about a nice gas-engine V6 ML320 or a V8 ML500......several years old, for WAY less coin than the premium of the newish ML CDIs?

The beauty of the PP forum AND the longish track record of the (gas) MLs, the improved MLs of the mid '00s years.....I think a lot of value can be derived from a gasser ML - serious here... PP's insight of the gas ML is valuable, and something to tap into here. The ML is not a cheaply made POS - but, it can cost some coin to fix - what better than to get one with some age on it at a big discount? Makes sense to me.

I keep remembering how it felt to sit in a new ML in the MB dealer's lot in New Orleans (Metairie) LA. when down there in about '00/-01 in my '99 E300 while travelling down there. The ML's driver's seating was to die for! OMG, was it comfortable.....kind of like the 06 CDI, but an upright seating of a big, full-sized MB SUV.

To me, I'd strongly consider the gas ML - several years old in very good condition with lower miles,. It just depends on your outlook and considerations for an MB SUV. The full-sized ML MB SUV would inspire a lot of driving confidence Up in the North Country - especially in the bitterly-cold, and horrific winter driving conditions you'all are faced with for months out of the year. They feel BIG on the inside too! Great if you got a couple kids to haul or a big dog.

Just an idea.....

jay_bob · #8 02-13-2014, 09:34 AM

Gas powered is going to kill you on fuel costs.

I went to Fuel Economy and did a side by side comparison of a 2008 ML320CDI 4matic and a 2008 ML350 4matic. Same vehicle except for the engine.

Diesel gets 18 city, 24 highway, 21 combined. Similar to my experience over the last 6 months.
Gas gets 15 city, 20 highway, 17 combined. And it needs premium, which around here is within 10-15 cents of the price of Diesel. It's been $3.529 for Diesel at the station near my house and premium unleaded is in the high $3.30s to low $3.40s.

(I know there are differences in this due to tax structures in some states. That is how it is in SC.)

The most telling figure from all the data on the site is the fuel cost to drive 25 miles:
Diesel: $4.61
Gas: $5.38

And the range and estimated dollars to refill the tank
Diesel: $87 to go 474 miles
Gas: $84 to go 384 miles

You learn to hit "debit" on the pump, or else you will hit the $75 Visa fraud cap if run as a credit, with this vehicle.

I am a firm believer in Diesel power and I believe it is a tragedy that it is not more widely adopted here. I know the market forces (can you say GM) and political reasons (EPA, ULSD, and all the rest), and don't want to get into those here, but it's still a shame.

jcyuhn · #9 02-13-2014, 10:41 AM

I am not a fan of the OM642 V6 diesel used in the ML (and many other Mercedes models). The reason being it has two common and expensive repairs. The first is a leaking oil cooler, located deep within the "V" of the engine. The typical repair cost is $2500. The second is the intake port shutoff motor. The OM642 has throttle flaps in the intake manifold. They are used to create manifold vacuum to increase EGR flow. EGR is used to control NOX formation in these pre-Adblue vehicles. The motor frequently fails, typical repair costs are $1500. You can google up discussions on these repairs and make your own decision on how frequently or rarely they occur.

Using the numbers from Jay-Bob above, you would save $400 per year in fuel costs if driving 12K miles per year. (Savings would be less here in Texas.) So the throttle motor repair wipes out 4 years of fuel savings, and the oil cooler 6 years.

What is the market price of a diesel vs. ML 350 gasser? I would expect the gasser to be somewhat less expensive, given the supply is so much higher.

BTW, I own an E-class sedan with this V6 diesel engine, so I'm not just bashing it. Love the way it drives, but from an economic perspective I just don't think it makes sense in the U.S.

BenzBob · #10 02-13-2014, 11:10 AM

I own a 2006 ML350 (gas) and typically get 21-22 mpg with mixed city/highway driving. On the highway, I am getting 24-25 mpg. Not a hyper-miler but am gentle on the gas pedal.

I have driven a 2010 ML 350 BlueTec (Diesel) and have not been able to get more than 28 mpg on the highway. The emission systems on the new BlueTec's are so complex that I would not own one. Add in Run-Flat tires and no spare tire and I am really not interested.

Personally, I would only consider the gasser ML as there is no way (even with better gas mileage) that the Diesel would be less costly to operate.

The only positive consideration would be higher low rpm torque if you were using it to tow. However, it is still not worth the extra maintenance and repair expense of the diesel engine.

BenzBob · #11 02-13-2014, 11:15 AM

One other point....if you don't drive it at least 15,000 miles per year, the extra cost of a diesel will never pay back.

Also, they only get great fuel mileage when you run them long trip distances on the highway. Short trips around town will give you better mileage with a gas engine. You have to run them "hot" to get the great mileage.

crazy4diesel · #12 02-13-2014, 12:23 PM

Unlike others I'm not so much a downer on the engine, versus a gasser, because I think diesels have benefits beyond fuel economy alone. I'd be more down on the ML or even GL in general. The plant at Tuscaloosa in my opinion has never produced true Mercedes quality product. The suppliers of the plastic interior components, are unique to that plant (cheep) when the first ML came out, and the "merger" announcement came out with Chrysler, there were some automotive journalists commenting on the quality of the ML especially the interior and wondering when did the merger really happen. My own article on the first ML was headlined "How Bright Does the Star Still Shine?" The ML has never ranked high on external CSI or even internal CSI. But, if it's a "package" you must have, and you love Mercedes, there's just not much choice is there?

GregMN · #13 02-13-2014, 12:39 PM

Thanks again for your replies and advice.

This vehicle will get driven 20 to 25k / year.
If I get it, it will be running on WVO.

I will make sure that the oil cooler seals have been updated to the viton ones.

The front runner ML so far is:
a one owner,
125k
dealer maintained w/records,
transmission replaced @ 95k,
new tires,
Southwest, vehicle.

But we are still shopping and are leaning toward a E320 CDI.