Instead of wondering, there's lots of youtube videos that will tell you how to check to see if the balance shaft is going or not. The gears really get worn down and I think there's some inspections to see if the letterings are centered or not. There are various theories that it only affects 10-30 percent depending on who you listen to and of course the others that say it could be 100%. The truth is somewhere between those but probably only MB really knows and they haven't really said. I hear the 10% from people who work at dealerships that say that they don't do that many of them but maybe that's because people don't want to pay for them. The 100% camp probably mean to say that there's no safe mileage where it won't go. There are threads on here with people who have higher mileage than yours that have went.

 

Well said, and good advice.
I've asked other's mileage, wondering if my 139K is just a fluke, or if there's any reasonable chance of reaching 200K without it blowing up.

There's quite a difference between 'maybe' 10-30% and 100%. I just hate the feeling that I'm playing Russian Roulette. I've never done well at gambling.

I couldn't get a copy of the VMI, but I was able to confirm through MBCA club sources that the VMI shows NO history of shaft repair. So, I know I'm still a target to get shafted by MB.

I invested in an iCarSoft MB V2.0 OBD II scanner to read codes. So far nothing cam related. Good tool to have anyway.

Apparently, removing enough engine parts for a visual inspection of the sprocket is quite labor intensive. However, I'm wondering if there's a way to get a small bore-scope in (I have one for inspecting 22cal rifle barrels). Possibly thru an opening that might require less parts removal? These modern bore-scopes are lighted and magnify the digital image to view on a laptop computer. Has anyone done this successfully to see IF, or how badly the sprocket has worn?

 

Let's at least try to settle the question of whether 100% will prematurely fail.

These 06-07 vehicles with the 350 V6 are now about 15 years old. Using a conservative average of 12K/yr. there should be many with over 180K now.

Has ANYONE made it past 200K miles or 300K kilometers without replacing the balance shaft sprocket due to premature wear, replacing the engine or junking the car?? How about 180K? 165K? Anyone?? Did the 100's of thousands of these faulty MB engines blow up already??

 

Let's at least try to settle the question of whether 100% will prematurely fail. These 06-07 vehicles with the 350 V6 are now about 15 years old. Using a conservative average of 12K/yr. there should be many with over 180K now. Has ANYONE made it past 200K miles or 300K kilometers without replacing the balance shaft sprocket due to premature wear, replacing the engine or junking the car?? How about 180K? 165K? Anyone?? Did the 100's of thousands of these faulty MB engines blow up already??

I have M272, 2008 which was out of the affected zone. I got 166K miles now and see no issue to keep it until 200K, especially after replacing bank 1 intake cam adjuster—which also gave DTC 1208 but not balance shaft. If your engine survives to 139K, it will likely to go longer on balance shaft. Other components is another matter.

 

2007 E350. 166k miles. So far, so good.

 

Based upon your VIN# to lookup your engine number..... Mercedes VIN Decoder | Decode Your Mercedes-Benz VIN
Do you know if the last 6 digits of your engine number falls into the range MB admitted were problems??

"M272 Engine Up to Serial No. 2729..30 468993 the material for the balance shaft sprocket and the timing chain guide wheel (idler) was modified on engines past these serial numbers."

 

My 06 E350 with the M272 350 V6 has 139,000 miles, so far NO cam fault codes or engine failure YET.
This engine with faulty balance shaft was used across many 06-07 MB models, and it's been said that ALL will eventually fail.
Many failed fairly early, still under MB Warranty. But I'm wondering WHEN those like mine that have survived are likely to fail.
Yes, I know you can check your engine number to confirm it's in the BAD batch. Mine is, and I think most if not all 06-07's are too.
Anticipating a $6,000-$$8,000 repair that requires complete engine removal and tear-down....or junking the otherwise beautiful car.

Obviously, it's somewhat dependent upon the frequency and quality of oil/filter changes.
I've been advised to go 1/2 of the 'MB suggested mileage intervals' which I've done since purchase 4 years ago.

Are there any other HIGH MILEAGE SURVIVORS out there?? At what mileage did YOURS fail??

As a master that repair at least 30 bad engines of this type can tell you to keep changing the oil every 3500 miles with a full synthetic Mobil one 10W40, Also if you change the timing chain and the pensioner with updated one you can prevent the demaging of the engine because the problem start from the stretched chain and bad tensioner.

 

Thank You for your info and experience.
I had been wondering if there was anything that could be done to slow the process (in addition to changing the high quality oil frequently and fleece filter).
It makes good sense that a new chain and tensioner would help to keep the cams within spec. I also heard about using a magnetic drain plug to pick up any shavings.

Do you suggest changing cam sensors when chain and tensioner replaced?

 

If the failure stems from sprocket wear, how does a new chain provide peace of mind?

Sixto
05 E320 wagon 173K miles

 

You worry too much. Is the check engine light on? No? Then keep driving.

This is not an imminent catastrophic failure, it's a very small, gradual failure over thousands of miles, and the earliest warning signal is a CEL with P0011/16 and P0012/17.

Again, let me reiterate in case the first line didn't get through -- you worry too goddamn much.

 

HaHa, You think I worry too much. Maybe so.

But it was a wise man, Ben Franklin who first published a quote in his timeless Almanac........."A stitch in time, may save nine!".
And another famous quote..."A smart man learns by his mistakes; while a wise man learns from the smart man!"

Knowledge is priceless. No worries!

 

My 06 E350 with the M272 350 V6 has 139,000 miles, so far NO cam fault codes or engine failure YET.
This engine with faulty balance shaft was used across many 06-07 MB models, and it's been said that ALL will eventually fail.
Many failed fairly early, still under MB Warranty. But I'm wondering WHEN those like mine that have survived are likely to fail.
Yes, I know you can check your engine number to confirm it's in the BAD batch. Mine is, and I think most if not all 06-07's are too.
Anticipating a $6,000-$$8,000 repair that requires complete engine removal and tear-down....or junking the otherwise beautiful car.

Obviously, it's somewhat dependent upon the frequency and quality of oil/filter changes.
I've been advised to go 1/2 of the 'MB suggested mileage intervals' which I've done since purchase 4 years ago.

Are there any other HIGH MILEAGE SURVIVORS out there?? At what mileage did YOURS fail??

Welcome to Ask 8-Ball, The Ultimate Online Oracle

 

I ordered this magnetic drain plug yesterday. I'll install it this week, and start watching carefully to see if I pick up any fragments when changing oil again in 2-3,000 miles.
Next, I'll do visual cam alignment inspection; and may feed in a new chain and tensioner for good measure. I know, some of you guys think I'm nuts and should just roll the dice and drive it into the ground; but the darn car is so nice otherwise; if I can take simple measures to protect it; why not? .I've taken several MB's to over 500,000km without having to even remove a head. I'm going to at least try to get this m272 to 200k miles (300,000km).I don't give up easily.

 

Just keep driving it and stick to the 5k mile oil change interval we discussed previously. If you really want to keep the car long term, keep an eye out for an 08-09 engine. A cheap low mileage example will pop up eventually. I think that's the best option.

 

Yes, probably the best long-term solution. I'm seeing them in the $2,500-$3,000 price range now, but best to be patient and wait for a good one.

Now with magnetic oil drain plug; when I change oil again in two months I should get some indication if the sprocket is shedding metal. I'll update post for anyone else in the same boat.
Meanwhile.....I'll keep on truck'in. It's otherwise a beautiful vehicle that does everything I need it to. And nothing newer seems much better. Unless I could go back a year or two and find a pristine RWD 2004-05 E320 with a bullet-proof m112 and 722.6 tranny combo in the right colors.

 

Have we established that the sprocket is ferrous?

What would metal particles in the oil tell you? How would you know they’re from the sprocket? Oil analysis is more informative. But you’ve already heard there’s a built in timer - ~10k miles from CEL. Nothing to do but enjoy it until then.

Sixto
05 E320 wagon 173K miles

 

The timing chain balance shaft sprocket is supposed to be a hardened material. Am I wrong in assuming it's a steel alloy; that a magnet would attract it's shavings?

Metal shards in the engine oil picked up by the magnetic drain plug would not be a good sign of engine condition; no matter what the source. Of course, no shards on the magnet doesn't mean I'm in the clear either. Anyhow.....I'm just looking for an earlier warning than the CEL light-cam fault codes. Once that happens; I couldn't even sell or trade the car for anything decent.

Some folks claim that not all the engines in the 'bad' numbers actually had a bad balance shaft sprocket. And Mercedes hasn't told us, so now it's our game of Russian Roulette.

IF in the meantime I find a really good 04-05 RWD E320 wagon; my other option is to trade out.

 

At one point it was guestimated that up to 35% of the engines were affected,
but there was never any real data to back that up.

 

That's exactly my concern. Some say 20-35%; yet some say 100%. Only MB knows; and they aren't telling anyone.
IMO MB is deliberately concealing the facts. With many hundreds of thousands of engines affected, they got away with a terrible design and quality flaw.
And, don't believe the problem stops at the engine number they threw out there. My mechanic has seen several balance shaft failures in 08 engines supposedly well beyond the 'number'. The fact that the only way to access the replacement of this acknowledged faulty part is from the rear of the engine; requiring complete engine removal and tear-down....SUCKS!

 

Is it normal for the 'live' cam position reading to be fluctuating .20 to .30 degrees min to max; or is that in itself an indication of loose chain sloppiness?
Just trying to learn something. The OBD II tool is only useful if you know how to interpret the readings.

I guess I can also try the visual alignment method shown in the Utube videos above.

 

I guess I can also try the visual alignment method shown in the Utube videos above.

Do you think looking down those holes you will be able to pick up .20 degree deviation?
So, actual values are a lot more precise. To find out what the limits are we need samples from engine that has set permanent codes for both intake and exhaust cams in retarded direction.

 

It's fine. ECU is constantly adjusting the timing, even at idle.

 

 

HaaHaa!
58,547 more miles to go and I might be the first guy in history to drive my m272 engine over 200K miles! WhooHooo! 🤪

 

Not meaning to rain in your parade but there are lots of 2006/7 M272/3 owners out there that aren’t part of this forum.

Sixto
05 E320 wagon 175K miles

 

You do know I was being facetious.
I'm actually hoping there's a lot of 06-07 m272 owners out there somewhere that have made it past 200K miles.
But so far, the silence is deafening.

 

I have several customers with 06 and 07 ML350, R350 and C300/C350 with over 200k.

Granted, post balance shaft replacement....

 

Mine was serviced at same MB Dealership until I bought it with 115K miles. No record of balance shaft replacement through Benz VMI. But....there was something on CarFax report about a 'Service Contract Claim' at 48,719 miles, 4 months after it was purchased by a 2nd owner. I've suspected that might have been balance shaft replacement under a secondary service policy, but MB dealer is completely mum. I dunno, but I'm feeling lucky! 🤞

 

How long for the CEL to come on after resetting? You’ll pass a sniffer buy they won’t even do an OBD test if the light is on.

Sixto
05 E320 wagon 190K miles

 

My CEL light comes on within about 10 minutes. I'm gonna have trouble with the DEQ. It's a shame, because I do feel like my 2007 E350 will run for a lot longer. It's been a fantastic car and really low miles at just 88K and 15 years old. No dents, beautiful inside and out. Just replaced the Airmatic suspension on it too...
Hoping I can petition the DEQ to make an exception. I don't think they can force me to spend $5K on repairs for a check engine light. I guess I'll find out soon. My plates expire in August.

 

As a former dealer, I was careful to avoid these vehicles. I used a web site to check the engine number against the VIN and simply did not buy those with the balance shaft issue.

My 2008 model E550 has 130k miles and is smooth as butter, but is not part of the engine number with balance shaft issues. In the shop, we did two of these on the E350 engines. Both required major disassembly and took a couple of days to. do "right". In the end, we had two ultra clean E class sedans that made great cars for people. We poured a ton of money into each to make them right.

There is no other option but to pull the engine and disassemble the assembly, replace the parts. We replaced all of the timing components.

 

They can't force you to fix the car but they can withhold the registration. Many people are faced with the same issue, fix it or junk it.

 

I have an Australian delivered CLK350 build 2005 and with engine number before the #272960 30 895140.
My engine light came on at around 200,000km (125k miles) and the codes 1200 & 1208.
My mechanic confirmed it is the balance shaft issue.
I asked how long before it goes bang?
He responded "could be 1 month, or could be 12 months, you can't predict when it will go, but it will start to run roughly - which I can feel slightly now".
He said the cost to fix is somewhere between $5-$6K (AUD) - yes engine out etc.
The car is realistically worth $8-$10K (AUD) as a private sale, but worth more to me.
I have regularly serviced it using 0-40W synthetic oil always.
I've had it for 12 years and always looked after it and has driven like a dream.
Its disappointing, but it's 17 years old so I will just keep driving it until it stops and then sell it to the wreckers for $500 (AUD).

 

From a few threads where the owner decided not to fix it, it seems it ran for a few thousand more miles, but then one day when you go to start it, it will be so bad that it basically won't start so you'll end up stranded somewhere, hopefully that's just at home. As other mentioned, it might be cheaper getting a used engine and doing a basic swap. The 2008/2009 models don't have the issue, some early 2007 models also had the issue so you have to go by the vin number, but there were still a few sensors on the 2007 models that went that didn't go on the 2008/2009 models.

 

How about sourcing a good used 08-09 engine?

Sixto
05 E320 wagon 190K miles

 

Mine is 2009, CGI, 270.000km, no idea if it was replaced or not, the engine number is way after the ones with problems, but you never know. Anyway, is running fine and no codes related to timing. I have other issues, with MAF/NoX and the secondary air pump.

 

I know this is an old thread, but I have an '06 M272, part numbers in the dreaded failure range, 2.5L with 313K on it and still running well, cam compensation values are still where they are supposed to be.

 

Old thread but a good thread! I'll weigh in on the theories about the cause: between the timing chain and the camshaft sprockets [edit - meant to say balance shaft sprocket, but same theory would also apply to camshaft sprockets] , one or both is too soft. As the timing chain wears, it becomes longer, and then it no longer fits the spacing of the teeth on the sprockets. This causes the sprockets to wear. I've replaced the timing chains on several of the older diesel engines, it is well known as a preventative on those engines to get another 200k or more miles. The majority of the diesel folk on the forums believe that frequent oil changes with high quality synthetic oil will reduce that chain wear, but the owner should be frequently checking the wear on the timing chain and when it approaches or exceeds 5 degrees, the chain must be replaced. If this common wisdom and theory also applies here to this engine, then I think frequent oil changes using high quality oil would be very appropriate, and also replacing the timing chain BEFORE the problem presents itself. If the stretch of the timing chain can be easily measured, then add that to your annual maintenance checks and start keeping a log.

 

Old thread but a good thread! I'll weigh in on the theories about the cause: between the timing chain and the camshaft sprockets, one or both is too soft. As the timing chain wears, it becomes longer, and then it no longer fits the spacing of the teeth on the sprockets. This causes the sprockets to wear. I've replaced the timing chains on several of the older diesel engines, it is well known as a preventative on those engines to get another 200k or more miles. The majority of the diesel folk on the forums believe that frequent oil changes with high quality synthetic oil will reduce that chain wear, but the owner should be frequently checking the wear on the timing chain and when it approaches or exceeds 5 degrees, the chain must be replaced. If this common wisdom and theory also applies here to this engine, then I think frequent oil changes using high quality oil would be very appropriate, and also replacing the timing chain BEFORE the problem presents itself. If the stretch of the timing chain can be easily measured, then add that to your annual maintenance checks and start keeping a log.

Is there a way to determine if the chain wears more than 5 degrees, from what? You might have a point about sprocket and/or chain too soft? In my case, the chain looks fantastic at 165K miles; the sprocket does show wear—but to my experienced mechanic, he thought it’s OK. However, in the end, replaced that sprocket fixed my problem that otherwise all other mechanics included MB dealers thought that the balance shaft!

 

I think it’s terminology. It’s well understood that the issue is with the balance shaft sprocket but expediency reduces that to just “balance shaft.” Balance shaft sees no stress or cause for wear as long as there’s oil pressure. Same issue exists in the M113 V8 which has the same sprocket on a jackshaft since it doesn’t have or need a balance shaft but it’s still called a “balance shaft” issue.

Sixto
05 E320 wagon 191K miles

 

No, no, no. You still think of the balance shaft sprocket—which there is no dispute. However, what I was referring to is the VVT cam adjuster sprocket—which plays a major role—and which might show DTC 1208/1200 too. Had owner known that replacing cam adjuster sprocket would have solved their DTC 1208/1200, do you think they still go the BS sprocket route?