Applicable Models (Not Applicable to Model 164.156, 204 or 216.386): Equipped with M272 Engine Up to
Serial No. 2729..30 468993 or M273 Engine Up to Serial No. 2739..30 088611.
The material for the balance shaft sprocket and the timing chain guide wheel (idler) was modified on
engines past the serial numbers listed above.
the ... represents 'any number'
Courtesy Efair
Added by jbanks15:
Balance Shaft Gear Issues
M272 engines that were sold between 2004 and 2008 with engine serial numbers below 2729..30 468993 often show early wear of the balance shaft gears, requiring extensive repairs at a retail cost of over $4000. These complaints led to a class action lawsuit against Mercedes Benz (Greg Suddreth and Paul Dunton v. Mercedes-Benz USA, LLC), which alleged the M272 engines are equipped with defective balance shafts gears which "wear out prematurely, excessively and without warning, purportedly causing the vehicles to malfunction, the check engine light to illuminate and the vehicle to misfire and/or stop driving." The suit further alleged that Mercedes knew of this problem, sending out repair bulletins on how to address this issue and ultimately changing the balance shaft gears to avoid this problem. This suit was ultimately dismissed with the judge agreeing with Mercedes that because the gears fail at 60 -80K miles and outside of the warranty period, Mercedes is not legally responsible for these problems. A second class action lawsuit is being organized. [7]
7. "Mercedes Benz named in class action over safety issues related to its M272 or M273 engines". Retrieved Mar 12, 2013. http://gotaclassaction.com/mercedes-benz-named-in-class-action-over-safety-issues-related-to-its-m272-or-m273-engines/
**
Do the video test to see if you have the issue, posts 106 and 117 and here
from Michael H.
Here is Notice of Pendency and Proposed Settlement of Class Action attached
see last pages of this thread for discussion ***
The Balance Shaft/Idle Sprocket settlement was approved by the court
post 156
Read the court document Class Action Settlement Claim Form - PreMail ****
FCPEuro is my first choice for on-line MB and Volvo parts. They just published this guide for common problems with the M272/273 engines and I thought everyone here would find it interesting. It is a nice summary of many topics that are covered here on slkworld.
My engine (272963 30 003441) seems to fall within the range. If I were to encounter balance shaft issues what would the symptoms be, and what could I do to be proactive against it?
My engine (272963 30 003441) seems to fall within the range. If I were to encounter balance shaft issues what would the symptoms be, and what could I do to be proactive against it?
Often there are no major symptoms until the CEL comes on. If you have STAR, you can periodically check for codes relating to cam bank timing issues. Other than that there is the visual inspection technique for checking the cam bank timing marks are still aligned (search on here for link to video).
Not much you can do to be proactive about it - if it's going to happen, it's going to happen.
Often there are no major symptoms until the CEL comes on. If you have STAR, you can periodically check for codes relating to cam bank timing issues. Other than that there is the visual inspection technique for checking the cam bank timing marks are still aligned (search on here for link to video).
Not much you can do to be proactive about it - if it's going to happen, it's going to happen.
Engine must be removed from car and I think other parts are also required to be changed while it is out. At some point Mercedes actually put together a kit of parts needed to address the issue. Google and you should find it.
I believe the labour component of the job is north of 50 hours. Total cost figures I have seen reported vary between $4K-$10K.
My invoice shows the balance shaft kit at $465 USD. Motor mounts, head gaskets, intake gasket, tensioner, breather cover, cam sensors, cam actuators, and fluids brings the parts tally up significantly though -- to about $1400.
Applicable Models (Not Applicable to Model 164.156, 204 or 216.386): Equipped with M272 Engine Up to
Serial No. 2729..30 468993 or M273 Engine Up to Serial No. 2739..30 088611.
The material for the balance shaft sprocket and the timing chain guide wheel (idler) was modified on
engines past the serial numbers listed above.
Found this amateur video showing exactly what a worn balance shaft looks like and its location within the engine. Also gives tips on repairing the job yourselves... yeah, good luck.
Seems like very low mileage for this to be showing up. What are the symptoms and what has been done to confirm the problem? Is a second opinion warranted? Since you just recently purchased the car does the seller share any obligation here?
I have asked my local MB service manager to ask MB if there is a possibility of contribution towards this known problem, but he does not hold out much hope as car is more than 6 years old :-(
Seems like very low mileage for this to be showing up. What are the symptoms and what has been done to confirm the problem? Is a second opinion warranted? Since you just recently purchased the car does the seller share any obligation here?
Wife drove home today from running an errand, describing the rough running and CEL that came on - I fear the sprocket issue is saying, "Hello!" Our SLK350 has about 41,000+ miles.We'll be taking it in tomorrow.
Didn't have luck searching but I apologize if this is answered already...what I'm curious about is did Mercedes come out with an improved sprocket to replace the problematic one? Is there a part number revision from the old part number that confirms there is a change? Just would like to know if this is going to become a "regular replacement part" to be aware of, or the fix is a long term/permanent solution.
My invoice shows the balance shaft kit at $465 USD. Motor mounts, head gaskets, intake gasket, tensioner, breather cover, cam sensors, cam actuators, and fluids brings the parts tally up significantly though -- to about $1400.
so i think it would be the parts kit n not just the sprocket.
i checked epc and there is no new 'shaft/sprocket' replacement number i can find
Ooo man, that doesn't give me the warm fuzzies. I'll give up thinking about it until tomorrow - no sense in wasting the last hours of a long holiday weekend dwelling on it. Jeff - your powers of replying to all these posts - amazing! Thanks!
Don't panic -- the balance shaft symptoms aren't "sudden onset" like this; plus there are specific codes for the problem. Have your codes read and cleared for free -- most parts places offer this service (just be sure you write them down before they're cleared). Let us know what they are.
It seems only Mercedes knows the statistics on this sprocket failure. The teeth wear occurrence is sporatic; I've found the mileage range to be from 20k-120k. How are some cars having this issue at only 20k miles?
My trusty mechanic says if you use a good oil (not Mobil 1), and change your oil every 5k miles, you will not see this sprocket wear problem. The main goal for engine oil is to prevent wear of the internal metal parts. There is a reason why Mercedes updated the oil change interval from 12k miles to 5-6k miles.
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