cyeung65

After putting on 2k miles on our new R class, the engine noise and vibration seems to be getting more intrusive - or maybe I am just getting more annoyed by it. There is an exhaust drone and engine vibration that is particularly noticeable at about 50 mph steady 6th gear part throttle on smooth asphalt.

Is this normal or is a there a fix like an engine mount or dampener that needs attention?

What are your impressions of the engine noise and vibration on your R class?

R. Reyes

smooth as glass and quite except for some tire noise. I do believe this was a problem with someone else's R as well. I would search and see if it got fixed.

cyeung65

Thanks - now I know I am not crazy. I could not find such a post with the search but seem to recall something like it. Please let me know if you find it.

ct_r500

Check the other site (benzworld) under this thread:

rosswell

Yes it's normal. ... I have the same intermittent thing and I've learned to ignore it - depends on outside temperature and usually during a warming phase while beginning a trip. It's probably exhaust related vibration and nothing to be concerned about. On mine it goes away after it's completely warm.

Same idea as the occasional quick shifts up or down at certain speeds while coasting...I've learned to drive differently to "help" the transmission know what comes next (since I don't have a PDK! like in a Porsche).

Cheers. Don't sweat the small stuff.

VelociRaptor

Thats one problem you run into in making such a quiet vehicle, any little thing that does make a noise is amplified by the quiet background.

R. Reyes

+1

cyeung65

Nearly a year after posting this, I want to check to see if others have this same concern about engine noise.

The noise I am experiencing is not temperature related to warm up nor is it intermittent. I hear engine exhaust noise whenever I accelerate. Granted this is a quiet car, and any noise can be intrusive, but it sounds like it has hot rod mufflers on it. That's great for a sports car, like my Corvette, but come on, this is a 50K luxo barge.

I even had it checked by MB and they said all is well.

I have gotten used to the noise, but recently, I bought a new Q7 and it is quiet as the dickens. The R350 sounds like an 18 wheeler in comparison.

Are all R350s the same as what I am experiencing?

bzliteyear

My R500 engine accelerates fine but is not smooth sounding like typical V8, or even the newer 4.6 or 5.5 liter V8 - but dealer says normal...so Ive been living with it, but certainly don't think it should be this way...it sounds raspy, from 1500 rpm to about 3k rpm.
PL

lkchris

If it's something fairly common, MB would likely have a DTB (dealer tech bulletin) on it. (Others call these TSBs)

Service advisors are not always aware of every bulletin.

For $18 for a 24-hr subcription, you can view all the DTBs there are. Also all the recalls, service bulletins, etc. Plus the equivalent of the entire service manual.

http://www.startekinfo.com

I subscribe and check it all prior to every regular dealer visit.

termite

AFAIK there is no DTB or TSB on the M113 V8 being fairly noisy, but it is a pretty rough engine nonetheless; especially when it is cold. there have been a number of forum members who have reported exactly the same thing on their R500s and mine is no different....for all of that thrashing at low rpm's though, it is reputed to be a very long lasting engine w/ proper maintenance.

cyeung65

Any viewpoints on the 350 V-6 engine?

lkchris

The early M272 V6 had a couple major problems

excessive oil consumption
failure of balancer shaft gear

Corrected in production

rosswell

Nice to revisit after a year ... Well, on mine to date there is no raspy rattle, only just some resonance noise when you slowly apply gas in a tall gear (at low rpm in 6th for example).

What I HAVE noticed is kind of neat (as I didnt notice it before) - but in the summer with the windows down, when I'm merging onto a high speed freeway (say around 140 km/h) using full throttle, it's as if there's an exhaust damper that opens up to allow blow-by that's not muffled - sounds like a race car but only under hard acceleration. (Think GTO with the vacuum actuated exhaust).

The resonance I spoke of above; could resonate other things as well. Haven't been bothered by it at all. However, anecdotally, when my car was new (I'm the second owner), the service dept. had it in for some warranty repairs that involved putting a shim plate in the exhaust to cure some rattles or noise.

All I've got - hope that helps. (I have the R350 V6 gas)

cyeung65

I wonder if there is such a bypass in the exhaust system. If there is, I would bank that the one on my R350 is stuck open.