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Rvliberty
12-21-2013, 11:51 PM
I have read a lot here about RSN. I may have it but I m not sure. I just had the 40k service so the fluid level should be okay. Mine happens at about 40 mph when accelerating. Question is...can this harm the transmission? What can be done about it?

Alan H
2011 Sprinter 3500 RV

TomLetsinger
12-22-2013, 12:08 AM
My understanding is that RSN happens under deceleration/coasting at moderate speeds. It won't harm anything, just a strange hydrodynamic effect in the tranny fluid. Nothing needs to be done about it unless it bothers you. The fix is effective but does reduce the efficiency of the transmission slightly. My 06 does it rarely so I just ignore it.
Others should correct me if I'm wrong.

MotoRepublic
12-22-2013, 02:24 AM
I have had some decent experience with the RSN. I have a 2006 3500 that started to suffer the RSN at about 130,000.. started as a light vibration and ended up being so bad it would literally shake a drink out of the cup holder!

A temporary cheap fix is pouring a tube of Mr. Tranny's Shudder Fix from O'Reilly Auto Parts in with the transmission fluid. Its like pouring molasses so be patient, you can even see it start to thicken up as it gets warm from the engine. This completely stopped the shuddering for about 5,000 miles and then it was back in gradual form. The second tube did nothing :/

A friend of mine has an 2008 2500 170" and after his started the RSN he was brave enough to try the trick of drilling a hole in a plate on the valve body assembly :o (which he said worked for a while but the noise is back)

The only true fix I found for my van was to fork out the $$$ and buy a 100,000 warrantied transmission from Silverstar Transmissions! They were awesome to deal with, the new transmission showed up in a purpose built box. We had the old one out and ready to go when the new arrived so we simply swapped them out and bolted up the crate to send the core back to SS. I have put about 50k on the new transmission and have had ZERO issues.

http://www.silverstartransmission.com/#!sprinters/c11x8

Hope that info might help. I wish I had just got the new transmission sooner rather than delaying the inevitable.

Dallas

thinice
12-22-2013, 02:59 AM
Not a expert, but since none have piped in, it is my guess that you are not experiencing RSN. As others have stated it usually occurs when decelerating and driving at low rpm's with a light touch on the accelerator. Mine has remained moderate for two years now & does not seem to be getting any worse. From what I have read the Dr. A fix is very effective for RSN. If you use the search box you will find tons of reading regarding RSN. You may have something else going on with your transmission. Wish I could be of more help.

Aqua Puttana
12-22-2013, 12:43 PM
I have read a lot here about RSN. I may have it but I m not sure. I just had the 40k service so the fluid level should be okay. Mine happens at about 40 mph when accelerating. Question is...can this harm the transmission? What can be done about it?

Alan H
2011 Sprinter 3500 RV
That sounds more like the shudder which is often related to old, spent transmission fluid.


http://sprinter-source.com/forum/showthread.php?t=5027&highlight=shudder

It can also be related to improper type fluid. There have been some mechanics, even dealerships, who think that ATF+4 is good for Sprinters. It is not. The recommended MB236.14 or MB236.12 is basically an ATFIII fluid. If you don't have MB236.14 spec fluid in there then it may be worth changing before going much further. Shell 134 fluid is one option.

Doktor A indicates very specifically that the DARF kit is not generally intended for the NCV3 NAG1 transmission. I wouldn't install it in an NCV3 without first checking with him.

vic

bbirdxx2000
12-22-2013, 02:00 PM
http://www.lubegard.com/SearchByCategory.aspx?CategoryCode=112&title=LUBEGARD+Automatic+Transmission+Fluid+Protec tant#


Problem solved:thumbup:

lindenengineering
12-22-2013, 02:28 PM
I have had some decent experience with the RSN. I have a 2006 3500 that started to suffer the RSN at about 130,000.. started as a light vibration and ended up being so bad it would literally shake a drink out of the cup holder!

A temporary cheap fix is pouring a tube of Mr. Tranny's Shudder Fix from O'Reilly Auto Parts in with the transmission fluid. Its like pouring molasses so be patient, you can even see it start to thicken up as it gets warm from the engine. This completely stopped the shuddering for about 5,000 miles and then it was back in gradual form. The second tube did nothing :/

A friend of mine has an 2008 2500 170" and after his started the RSN he was brave enough to try the trick of drilling a hole in a plate on the valve body assembly :o (which he said worked for a while but the noise is back)

The only true fix I found for my van was to fork out the $$$ and buy a 100,000 warrantied transmission from Silverstar Transmissions! They were awesome to deal with, the new transmission showed up in a purpose built box. We had the old one out and ready to go when the new arrived so we simply swapped them out and bolted up the crate to send the core back to SS. I have put about 50k on the new transmission and have had ZERO issues.

http://www.silverstartransmission.com/#!sprinters/c11x8

Hope that info might help. I wish I had just got the new transmission sooner rather than delaying the inevitable.

Dallas

Dallas
I suspect from your post that there was more going on in the "transmission works" than something that might have fixed the torque converter lock up clutch actuation than the popular "fix" originally posted /devised by Andy B for TIN's.

The transmission unit as a whole is very simple and remarkably robust in the realm of things and uses a different electric approach to getting speeds out of it. In short it is used in a lot of MB platforms incl the G Wagon.

The violent shudder you report could be a number of issues including the lock up clutch, torque converter, or in fact partial engagement/hanging on/overlap of multi plate clutches or sprags inside the running train.

As posted by Vic and myself others the right fluid is essential for smooth shifting and that's to state Shell 134 is not an easy fluid to locate on the parts shelf of your neighborhood "fwendly" parts store.
Fix in a can additives at best only delay the onset of a developing problem, or simply mask an issue so that you can flog the van to an unsuspecting buyer. That goop you used has little widespread acclaim, just complicates its removal when doing a tear down repair.---eeerk!

Silverstar does a good job for the money and I have recommend them on this forum before not only for a quality "reman unit" but the speed of turn around when a transmission is needed for a VOR.
This is especially so for the DIY'r as there is only about 5 hours of pro shop time allowed for a R&R TIN and 6 for the NcV3.
So whether you "DIY" it or have a shop install it there is about 5 bills involved as a charge if you farm the labor out.

For the handy DIY'r there are only a few precautions to take into consideration on the install.
1) Make sure the torque is bottomed inside the front pump--otherwise you will bugger up the pump drive.

2) Make sure the "nose" alignment boss on the torque converter isn't burred up or has corrosion on it and then in turn the crank female engagement sleeve. You must have a nice sliding snug fit as the torque converter slides home when stabbing the transmission unit.
This ensures the torque isn't loading the pump and second it allows you to turn the torque with you fingers to align the flex plate bolts.

3) Last and very important
Flush out the cooler lines BEFORE you connect them. Reason:-
If the original transmission has come apart, junk and or contaminated fluid will be lurking inside the cooler or it might even be plugged. So beware of this when installing a transmission---any freeking auto transmission.

Good to read the tranny worked for you.
Dennis

bbirdxx2000
12-22-2013, 02:45 PM
I used the Lubegard (Red bottle) it lasted about 10,000 miles. 2nd treatment rsn is gone again:thumbup:

lindenengineering
12-22-2013, 04:40 PM
Again additives only mask a problem or a condition.

Most speeds in a normal multi pack transmission are using a combination of steel and "faced" driven plates which believe it or not are a paper material----yes paper!

That's why we in the trade call one part of a repair kit "steels and papers".

Just take the steels for a moment; if you were to magnify the precision ground surface it would consist of a peak and valley surface created as the plate is ground/surfaced to finish on production.

In service the action of the papers rubbing over the steels just before engagement "tends" to bend the peaks over in the direction of operation allowing an increased level of slippage before clutch engagement. Looks like the peak of the Matterhorn or worse!
In "zee aulden days" Lubeguard was favorite "bung in a bottle fix" for simple hydro mechanical boxes but in today's electro-hydro mechanical units the controller conducts adaption to optimize application times.

In some cases bunging in a can of additive which consists mainly of a polymer fiction modifier above that of what is already in the fluid by the blender alters it significantly to get a satisfactory shift /apply performance.
In your case it works which is good, saves a tear down and fix.

The same I remember it being a good "fix' for a SCG Hydrocyclic bus transmission which partially applies the reverse pack to act as a retarder when going down steep grades by tying the pack up to create a controlled bind up condition.
The Voith DIWA does the same but they introduced a "pulse" apply ("thanks to electronics!) to eliminate the grab of applying reverse when going forward. (some of you might say Yikes!):crazy:

Now totally off topic, ZF the zen masters of transmissions use a reverse torque converter turbine activity to get a retard condition. Very simple in execution you have to ask why nobody thought of it before.
Designed by a Frenchman which might explain it all if you know Renaults.:rolleyes:OMG
Dennis

riskydnb
12-23-2013, 09:33 AM
The rsn vibration is directly related to an issue in the valve body of the tranny, you could just replace the valve body to permanently fix the issue instead of masking the problem. It is way cheaper than buying a whole tranny...

Eric Experience
12-23-2013, 10:05 AM
Alan.
Every case of vibration in the transmission I have had in my shop has been fixed by Cleaning the magnetic pick ups in the valve plate and using the correct MB supplied fluid. Eric

riskydnb
12-23-2013, 10:13 AM
Alan.
Every case of vibration in the transmission I have had in my shop has been fixed by Cleaning the magnetic pick ups in the valve plate and using the correct MB supplied fluid. Eric

That works for me about 40% of the time...but when the valve that relieves the torque converter pressure goes bad you have to do the Dr. A fix...