In these harder to make it times my sprinter just had to snap its second crankshaft.A LITTLE history for the mercedes mechinics on this site.IT all started at 185000 at royal gate dodge in st loui they put in a new torque converter and allis well until 250000 and the crank breaks destroyes the block,so we call andy and he makes up arebuilt short block and assemblies old head,we put it back in in my shop and she starts and purrs likekitten until 316000 snaps crank again, well got her hauled home again and pulled the moter out .we are thinking that torque converter is the problem but havent checked it all out yet, as had to buy a cheap chevy van to keep haulin so I THINK THAT I SHOULD GET WORST LUCK SPRINTER AWARD can anybody beat this??
Worst luck SPRINTER
- Thread starter breeze
- Start date
You are definitely a contender for the award
greg334
Veteran Expediter
Yes it can be beaten. I heard of five rear ends on 100,000 miles.
It sounds like the torque converter and flex plate and it is either out of balance or not properly installed.
I would have replaced the converter and flex plate the first time.
Are torque converter problems common on those great German precision machines?
It sounds like the torque converter and flex plate and it is either out of balance or not properly installed.
I would have replaced the converter and flex plate the first time.
Are torque converter problems common on those great German precision machines?
actually ummm Greg there can be...we call it The Torque Rumble..it is common in most sprinters at or around 35-40 mph while coasting. Some have it more then others and quiets down for awhile just after servicing....We don't allow it to rumble by either slowing down or speeding up a bit....
There is a more technical name for it...Steady Eddie knows more of this...
aileron
Expert Expediter
It's known as RSN or Rumble Strip Noise since it sounds like you drive over those things when you run off the road.
I have heard about RSN causing some engine damage, but never a broken crankshaft.
On my 2004 I had it pretty bad for about 50k miles after my last transmission fluid change, but did not cause any damage so far. Then I changed the transmission fluid to the latest MB 236.14 and I cleaned the valve body and the speed sensors in the tranny and RSN almost disappeared.
I have heard about RSN causing some engine damage, but never a broken crankshaft.
On my 2004 I had it pretty bad for about 50k miles after my last transmission fluid change, but did not cause any damage so far. Then I changed the transmission fluid to the latest MB 236.14 and I cleaned the valve body and the speed sensors in the tranny and RSN almost disappeared.
RLENT
Veteran Expediter
Not entirely certain, but I would imagine it does.
The torque converter clutch is an Electronically Modulated Converter Clutch, and can be applied in various gears (2nd thru 5th) and with varying degrees of engagement.
The torque converter clutch is never fully engaged - there is always some degree of slippage.
This is likely what causes RSN - it is inherent to the design of the system. It also explains why when old fluid (with degraded frictional characteristics) is replaced, RSN is minimized, or even eliminated (at least for some period of time)
That certainly possible.
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greg334
Veteran Expediter
It makes sense that this would be a cause, why doesn't it fully engage the clutch like other converters? GM and Opel come to mind. Is it a presure issue, like in some Chrysler transmissions where the pressure is too low to fully engage the lock up clutch and there is slippage in 4th gear?
It really sounds like a drive line shudder that happened in some MBs with I think ZF transmissions. I don't know what is in the sprinter, but it was an odd shudder about 25 mph.
It really sounds like a drive line shudder that happened in some MBs with I think ZF transmissions. I don't know what is in the sprinter, but it was an odd shudder about 25 mph.
Our RPMs are so low it feels like we are in too high of gear..and I can feel the drag or lugging.
Maybe when deceleraterating the tranny is still in a higher gear when the rpms are low...thats maybe why we either have to slowdown quicker or hit the fuel pedal a bit to get the rpms up
Maybe when deceleraterating the tranny is still in a higher gear when the rpms are low...thats maybe why we either have to slowdown quicker or hit the fuel pedal a bit to get the rpms up
The torque converter will seize on the crankshaft over time. It took two techs with pry bars to get mine off. One tech told me it is called torque converter shudder. The computer will learn the drivers driving style and adjust to it. If you drive for a while on the highway then spend time driving city the computer gets confused and can’t determine what to do. This also happens with more than one driver is driving the van. Two different driving styles. When drivers hear and feel the RSN (rubble strip noise), which is what they tell the tech, as that is what it feels like. Areas that have been looked at for this problem:
1. Drive shaft on the transmission side is bolted to the rear staff of the transmission. It was thought the shaft was loose and causing the RSN when slack was introduced in the system. The drive shaft is not serviceable and must be replaced if bad, all of them.
2. The drive shaft flange was bent where it bolts onto the transmission.
3. Value body and speed sensor were dirty
4. Fluid needed changing
5. Torque converter bad
I have noticed the RSN after I unloaded a heavy load, but after a few miles it goes away. Maybe the computer learning all over as I do drive a little different with heavy loads. Changing the fluids sooner than 80,000 miles has helped somewhat.
1. Drive shaft on the transmission side is bolted to the rear staff of the transmission. It was thought the shaft was loose and causing the RSN when slack was introduced in the system. The drive shaft is not serviceable and must be replaced if bad, all of them.
2. The drive shaft flange was bent where it bolts onto the transmission.
3. Value body and speed sensor were dirty
4. Fluid needed changing
5. Torque converter bad
I have noticed the RSN after I unloaded a heavy load, but after a few miles it goes away. Maybe the computer learning all over as I do drive a little different with heavy loads. Changing the fluids sooner than 80,000 miles has helped somewhat.
greg334
Veteran Expediter
Well Steady, I have had a lot of converters stuck on the crank where I would have to pry them off the flex plate.
You bring up an interesting point about the adaptive shifting within the trans ECM and what OVM said is an ECM issue; this is why I asked if it is just on this side of the pond.
You bring up an interesting point about the adaptive shifting within the trans ECM and what OVM said is an ECM issue; this is why I asked if it is just on this side of the pond.
Maybe that is why the natural self life of a tranny is between 350,000 to 450,000 miles...
I had 459,000 when mine just plain "wore out" End of its life cycle
I had 459,000 when mine just plain "wore out" End of its life cycle
greg334
Veteran Expediter
OVM, I got a stupid question for you about that, did the dealer tell you there was a core charge or did they just take the trans?
The reason I mention this is if you got a new trans, according to D-C a couple years ago, there is no core charge because these are new transmissions from germany and the trans is yours to do what ever you want to do with it. The dealer never mentions this and they go and sell the trans for a grand or so as a rebuildable to a rebuilder.
The reason I mention this is if you got a new trans, according to D-C a couple years ago, there is no core charge because these are new transmissions from germany and the trans is yours to do what ever you want to do with it. The dealer never mentions this and they go and sell the trans for a grand or so as a rebuildable to a rebuilder.
Mine ended up being a reman and I would be guessing it was a straight up exchange...There was no mention of a core charge or rebate.
When these trannys die it is a natural death there is no warning signs whatsoever...no slippage, no leaks, no burnt smell, nothing.
I was told there is nothing one can do to prevent it...It is just the end of its natural life span.
Happened to me and Eddie exactly same way
Now we wait and see what the natural life span of an engine is in North America...
Maybe Mercedes should have a sensor for sensitivity?*L*
I guess I could've posted Andy's thoughts....
Here at the Global Sprinter Research Center, I am happy to announce a cure for
Rumble Strip noise. Longer term 'Clinical trials' are now in progress and
looking promising.
Backround info- I was finally able to direct significant time and effort to
researching RSN when the PERFECT patient arrived in the form of a client 2005,
140" 2500 cargo with approx 62,000 miles.
This particular Sprinter had a history of recurrent limp home mode with codes
related to sporadic MAF sensor plausibility issues. The vehicle NEVER misbehaved
when visiting various dealers. My new client asked me to help diagnose the LHM
problem and to keep and use the vehicle indefinitely, until cured.
I did cure the vehicle of its LHM issues, and as luck would have it, this
particular Sprinter was coincidentally cursed with moderately severe, and more
importantly, predictable and easily repeatable RSN.
Since I was able to utilizing this Sprinter as my daily driver/shop truck and
was monitoring ECM sensor data for the LHM issue, I included additional TCM
instrumentation in the name of RSN research.
The findings- Several years ago (on a thread in the Yahoo Sprintervan
group) I identified the source of Rumble Strip Noise to be the TCC (torque
converter clutch). I had theorized that the TCC solenoid's modulation was
responsible for the torsional vibrations and then magnified by the Sprinters
vast body panels.
Using my research 'volunteer', I measured the TCC solenoid's duty cycle control
frequency at xxxHz. Remember, the TCC is NEVER fully locked, but operates in a
duty cycled slippage range of between 5-95%.
Mbenz's use of 'controlled' TCC slippage was intended to allow controlled
bypass of fluid to the transmission cooler so as to reduce temp of both the
fluid and the torque converter and IRONICALLY to dampen engine torsional
vibrations. I put the word 'ironic' in capital letters because under certain
conditions, the opposite appears to occur.
NAG1 variants are employed in numerous Chrysler vehicles and according to
factory tech literature, in most all of these vehicles, TCC activation (slippage
mode) is used ONLY in 3rd, 4th and fifth speeds. My data showed that the diesel
Sprinter engages TCC activation in ALL 5 forward speeds.
My instrumentation also clearly allowed me to observe the 2 operating phases of
the TCC- The 'ON' phase where engagement induces controlled slippage of between
5-95% and the 'OFF' phase where no TCC action takes place (100% slippage of the
TCC-in other words, deactivation).
I have concluded that RSN is not only the result of solenoid duty cycle
modulation but even more importantly, overly aggressive activation software maps
whereby TCC control is switched 'ON' at VERY low speeds and very light loads
(both accel and decel) resulting in the engine's torsional vibrations being
transmitted to the drivetrain (similar to 'lugging'). The opposite of what TCC
'slippage' was intended to prevent.
Being prevented from altering TCM software program maps, I used intentional
induction of TCM limp home mode to turn off TCC control and used the TCC
adaptation feature to manipulate TCC control intensity and was able to produced
useful data.
Experimentation with damping and modification of TCC solenoid action optimized
what I believe to be the best 'compromise' between fuel economy and TOTAL
elimination of RSN. The patient's transmission now behaves like a Mercedes Benz
'S Class' transmission, smooth and seamless.
Ongoing clinical trials will hopefully reveal any detrimental effects on fuel
economy and any mitigating effects of long term TCM adaptation in reducing the
efficacy of 'the cure'.
RSN may not be of great concern to highway expediters but any Sprinter owner
transporting people in stop and go traffic will agree it is UNACCEPTABLE in a
vehicle of this sophistication and pricing as well as a concern with regards to
long term drivetrain damage.
Stay tuned for updates. Owners suffering with severe RSN are welcome to inquire
about participation in further clinical trials. Doktor A
Here at the Global Sprinter Research Center, I am happy to announce a cure for
Rumble Strip noise. Longer term 'Clinical trials' are now in progress and
looking promising.
Backround info- I was finally able to direct significant time and effort to
researching RSN when the PERFECT patient arrived in the form of a client 2005,
140" 2500 cargo with approx 62,000 miles.
This particular Sprinter had a history of recurrent limp home mode with codes
related to sporadic MAF sensor plausibility issues. The vehicle NEVER misbehaved
when visiting various dealers. My new client asked me to help diagnose the LHM
problem and to keep and use the vehicle indefinitely, until cured.
I did cure the vehicle of its LHM issues, and as luck would have it, this
particular Sprinter was coincidentally cursed with moderately severe, and more
importantly, predictable and easily repeatable RSN.
Since I was able to utilizing this Sprinter as my daily driver/shop truck and
was monitoring ECM sensor data for the LHM issue, I included additional TCM
instrumentation in the name of RSN research.
The findings- Several years ago (on a thread in the Yahoo Sprintervan
group) I identified the source of Rumble Strip Noise to be the TCC (torque
converter clutch). I had theorized that the TCC solenoid's modulation was
responsible for the torsional vibrations and then magnified by the Sprinters
vast body panels.
Using my research 'volunteer', I measured the TCC solenoid's duty cycle control
frequency at xxxHz. Remember, the TCC is NEVER fully locked, but operates in a
duty cycled slippage range of between 5-95%.
Mbenz's use of 'controlled' TCC slippage was intended to allow controlled
bypass of fluid to the transmission cooler so as to reduce temp of both the
fluid and the torque converter and IRONICALLY to dampen engine torsional
vibrations. I put the word 'ironic' in capital letters because under certain
conditions, the opposite appears to occur.
NAG1 variants are employed in numerous Chrysler vehicles and according to
factory tech literature, in most all of these vehicles, TCC activation (slippage
mode) is used ONLY in 3rd, 4th and fifth speeds. My data showed that the diesel
Sprinter engages TCC activation in ALL 5 forward speeds.
My instrumentation also clearly allowed me to observe the 2 operating phases of
the TCC- The 'ON' phase where engagement induces controlled slippage of between
5-95% and the 'OFF' phase where no TCC action takes place (100% slippage of the
TCC-in other words, deactivation).
I have concluded that RSN is not only the result of solenoid duty cycle
modulation but even more importantly, overly aggressive activation software maps
whereby TCC control is switched 'ON' at VERY low speeds and very light loads
(both accel and decel) resulting in the engine's torsional vibrations being
transmitted to the drivetrain (similar to 'lugging'). The opposite of what TCC
'slippage' was intended to prevent.
Being prevented from altering TCM software program maps, I used intentional
induction of TCM limp home mode to turn off TCC control and used the TCC
adaptation feature to manipulate TCC control intensity and was able to produced
useful data.
Experimentation with damping and modification of TCC solenoid action optimized
what I believe to be the best 'compromise' between fuel economy and TOTAL
elimination of RSN. The patient's transmission now behaves like a Mercedes Benz
'S Class' transmission, smooth and seamless.
Ongoing clinical trials will hopefully reveal any detrimental effects on fuel
economy and any mitigating effects of long term TCM adaptation in reducing the
efficacy of 'the cure'.
RSN may not be of great concern to highway expediters but any Sprinter owner
transporting people in stop and go traffic will agree it is UNACCEPTABLE in a
vehicle of this sophistication and pricing as well as a concern with regards to
long term drivetrain damage.
Stay tuned for updates. Owners suffering with severe RSN are welcome to inquire
about participation in further clinical trials. Doktor A