Nag1 TECH ALERT

josephpampliega

New member
Technically your transmission did not 'go to neutral', it lost all drive.

Only a few transmission fault codes can result in intentional loss of drive and your 2108 shift P solenoid circuit code is not one of them. If the 2108 code did not reappear after the solenoid actuation test then it is likely an unrelated, older, stored fault code.

Did you replace the filter? I suspect fluid pressure is low. You should be able to check pressures with your DAS.

Doktor A
I replaced filter too with new one. I will go ahead and check pressure and post my results.

I hope the pump or torque conveter did not get destroyed for whatever reason as the level was correct prior to draining.

Thanks for the reply.
 

Kubbie

'06 2500 140" Std Roof.
Now, using the same T-30 Torx bit, you used to remove the pan- loosen all the bolts and remove all but 2 (opposing bolts) holding the valve body in place. Supporting the valve body carefully-remove the last 2 bolts and lower the valve body down and carry it immediately into your surgically clean(?) workshop.
A
I removed the 10 bolts and cannot drop the valve body. I also have adapter plug unscrewed.
Is there something I am missing that is preventing it from dropping? ( I put two back in to come inside to type this...)

Edit: never mind - need to learn to count to 10.
 
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mackconsult

New member
Wow I am surprised that I never noticed this write up. Thanks Dr A.

My sprinter has had pretty light use and sitting on 119k. Right after I bought it @ 67k I changed tranny fluid and filters. Planning on a tranny change again this summer so I will be sure to do my transmission plug and this procedure when I do it.
 

abittenbinder

Doktor A (864-623-9110)
Wow I am surprised that I never noticed this write up. Thanks Dr A.

My sprinter has had pretty light use and sitting on 119k. Right after I bought it @ 67k I changed tranny fluid and filters. Planning on a tranny change again this summer so I will be sure to do my transmission plug and this procedure when I do it.
I am now recommending this procedure (R+R of valve body for inspection and cleaning of the speed sensors) only when symptoms and/or fault codes are present.

Doktor A
 

Ro3bert

New member
Doctor A

With respect to the speed sensors gathering particles, is there any way to cover those magnets with some sort of plastic, something resistant to the transmission oil? That would certainly make cleaning them a cake walk especially if the plastic was removable.

Robert
 

abittenbinder

Doktor A (864-623-9110)
Doctor A

With respect to the speed sensors gathering particles, is there any way to cover those magnets with some sort of plastic, something resistant to the transmission oil? That would certainly make cleaning them a cake walk especially if the plastic was removable.

Robert
The speed sensors are Hall effect sensors, one of which is already covered with plastic. Transmission fluid does not harm the.

Cleaning them requires dropping the valve body and I now recommend cleaning is only necessary if corresponding fault codes are present and/or excess metallic debris is found in the pan.

Doktor A
 

calvin

Member
Haven't had any problems with my trans as of yet (240k).. but just wanted to thank everyone for the time and effort put into gather and posting this information. (btw, I've changed my atf fluid to amsoil and have had no problems for 40k :) )

Thank you all
 

mawsea

sprinter guru
It's back!!!!!!! so about A month ago I did the Fluid change to the shell ATF, the speed sensor clean and valve body clean, new connector and even did the DARF mod. The results were amazing.....for about a month. Now the shudder is back worse then ever. To be frank I've been reading these forums for the past seven years since the yahoo days. I really don't feel like re-reading every post on the RSN subject. So does anybody have an Idea why the shudder was gone and then reappeared?
So I took it into a Mercedes dealer today, thinking maybe it was just low on fluid or a code need to be cleared. Mercedes said I needed a new $1400 torque convertor. :idunno:
 

abittenbinder

Doktor A (864-623-9110)
So I took it into a Mercedes dealer today, thinking maybe it was just low on fluid or a code need to be cleared. Mercedes said I needed a new $1400 torque convertor. :idunno:
Ask the dealer to reset transmission adaption. Do not bother with any relearning procedure, just the reset.

Doktor A
 

jdcaples

Not Suitable w/220v Gen
There are several DAD scan tool owners in Seattle. You may be able to leverage the community to get a free, or substantially cheaper transmission control module adaptation reset than at the local dealership.

-Jon
 

abittenbinder

Doktor A (864-623-9110)
There are several DAD scan tool owners in Seattle. You may be able to leverage the community to get a free, or substantially cheaper transmission control module adaptation reset than at the local dealership.

-Jon
I have some anecdotal evidence from the field that the DAD's TCM reset of adaptation is not functional.

Doktor A
 

flman

Roadrunner, Genius of Birds ALWAYS WINS! NO FAILS!
I am now recommending this procedure (R+R of valve body for inspection and cleaning of the speed sensors) only when symptoms and/or fault codes are present.

Doktor A
I pulled mine with no fault codes or symptoms at 98K and found the solenoids to be absolutely clean.
 
I have an exploded view from Daimler that a local shop provided as they have never addressed this problem and we are learning together. (there nearest "dealer" for service is 80+ miles away).

The code they get is (among others not related) is y3/6N3 (RPM Sensor) no signal. I noticed an odd looking plug with 2 parallel slots, held in by a cir-clip at the top, rear of the trans near the output shaft. The drawing (referenced above) shows this as a "speed transmitter."

The van is lightly loaded and only has 37k miles. All wires ohm out properly. Does anyone know if this is where I should be looking?

Thanks much!
:thinking:
 
Still have **** issue but considering cleaning sensors n2&n3. The above "odd" plug at rear of tranny must be for a different application and is simply a plug where different type of speed sensor would be installed. With only 37k miles I plan to try and read the MHz of the sensors before R/R. I understand sensor output may not be availabe if currently in Limp Mode (no power out from TCM). Any input is appreciated. santafespecialties@comcast.net

Took frequency readings (RPM) from N3 speed sensor: all okay until: brought trans up to operating temp, let set for30 min then did stop an go driving. (This seems to be when failures occur). Sensor went from 1200 rpm to 52000 rpm while downshifting at stop sign. Truck went into limp mode and sensor went back to working. Im thinking it has something to do with uneven cooling/heating of plastic components fixed to metal: connector or defective electrical board (plastic) in valve body? Any ideas Doctor A?
 
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I have since learned the sensors are mounted on the plastic solenoid/electrical 'plate' inside the tranny. I wanted to make sure this was the problem before taking it apart so I connected a volt meter with a hertz setting on the sensor wires under the drivers seat where they connect to the TCM. Was able to see the '3rd' gear sensor give a false reading (did not closely match rpm's as usual) on downshift which also caused a hard downshift.
Removed the plate cleaned the sensors, drained the torque converter (let drain overnight) reassembled and it shifts like new ever since. All this information can be found in these threads.
After letting the old fluid set I found considerable more metal filings (microscopic) in the bottom of the container and would recommend draining the torque converter. The speed sensors weren't grossly dirty but seems it doesn't take much to cause problems. I'm hoping this was caused from improper break-in from the first owner (used fleet vehicle) and much stop an go operation from being in Chicago (where I picked up after purchasing on eBay).
Hope this helps and much thanks to everyone on this forum.:cheers::cheers
 

badvan

New member
can anyone tell what order the solenids go in to to the vavle body becasue on the bottom of the solenids there are number like c1,c2, etc
 

Coast2Coast

2006 158 Cargo
Doktor A

If your transmission is leaking in the front and you have a bad auto transmission pump 7222700197
would you think it's better to replace just the pump or whole transmission, how much labor can one expect when replacing trans pump on 06 Sprinter?
 

jcolvin

Member
Hmm. I've got 86,000 miles on my sprinter with tranny fluid changed out around 20,000 miles ago (OEM fluid). Very mild RSN but I'm starting to get the *occasional* hard shift (shifts with a bang instead of smoothly). I have already replaced the TCM electrical connector at the transmission (which was indeed leaking badly) after getting a temporary transmission LHM, since then no more LHM but still the occasional hard shift. Tranny fluid levels right where they should be measured by my dipstick. Is this likely to be speed sensor contamination? No codes.
 
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vanven

Member
-Has your Sprinter clocked over 80K miles?
-Does your Sprinter see severe "stop and go" service and clocked 50K miles?

If you answered yes to either question-I recommend you perform this additional procedure during your routine ATF fluid/filter change.

-Are you experiencing transmission related malfunction codes and/or symptoms of transmission malfunction despite having proper fluid level?

-Is your dealer recommending a transmission replacement?

If you answer yes to either of the last 2 questions-don't wait. Perform this procedure immediately.

Here's the procedure that has benefited "severe service" delivery fleets and I'm hoping will help group owners avoid needless transmission replacement.

If you answered yes to any of the above questions- I recommend you drop your transmission valve body (or as DC calls it ,"the electro-hydraulic unit"). It's simple to do and I'm recommending dropping it specifically for inspection and cleaning of the 2 circuit board mounted speed sensors.

Here's the procedure-When you have the pan off and the fluid drained (and inspected) and the filter removed-don't throw out the old filter just yet. It's halves can be uncrimped with a channel-lock plier and you can examine the inner filter media for unusual debris and accumulation.

Next -now is a good time to replace your trans elec. connector's socket O-rings since the socket needs to come out for valve body removal. Remove the small heat shield and disconnect the trans. elect connector. Reach into the trans. mounted elec. socket with a 7mm 1/4 drive socket at the end of a short extension-unbolt the retaining bolt and gently pull the socket out of the trans. Have a new socket with o-rings ready for later reassembly-part# is 68021352AA (inexpensive and comes complete with the latest black O-rings).

Now, using the same T-30 Torx bit, you used to remove the pan- loosen all the bolts and remove all but 2 (opposing bolts) holding the valve body in place. Supporting the valve body carefully-remove the last 2 bolts and lower the valve body down and carry it immediately into your surgically clean(?) workshop.

Lay the complete valve body on a clean newspaper- elec side up. Refer to your workshop manual diagrams- the speed sensors are easy to spot(on top) and should be carefully cleaned of accumulated metallic filings(they are strong magnets).

Inspect exposed parts of the circuit board and exterior of the solenoids for heavy accumulation-clean carefully.

If things look really clean- you don't need to go further. Skip down to re-installation.

If there's heavy accumulation of metallic debris you can unbolt(again-the T-30 Torx bit) the solenoid retainers and carefully remove the solenoids. The electrical board can now be unclipped(2 push clips) and separated from the valve body.

Inspect the small filter screens under the 2 regulating solenoids(If you find the screens clogged-I would stop here and seriously consider a transmission overhaul-this is thankfully rare) also inspect the o-rings on the 3 shift solenoids and single TCC lock-up solenoid(yes-part of the RSN gang). The o-rings are NOT avialable as (separate from solenoid) replacement parts from DC but any suspect o-rings can be replaced by visiting the local autoparts store and sorting through their collection of quality viton o-ring drawers.

If the circuit board looks hopelessly contaminated -it is available as a replacement part and is somewhat reasonable in price. It's mostly encased in plastic and cleaning can be tedious.

Reassemble the electro and hyd. portions and follow torque specs(71 in/lbs.) for the solenoid retainers.

Carefully lift the assembled valve body back into the transmission sump and make sure you engage the plastic sliding lever of the selector valve into the detent plate post. Torque the 10 bolts to 71 in./lbs. Install your new connector socket, and your new filter and sump seal. Bolt on the sump and fill as usual (I assume you have also drain the torque converter as per previous post). Photos show-1) The complete valve body. 2)Transmission w/valve body removed. 3)Close-up of speed sensors. 4)Disassembled valve body.5)Close-up of the TCC lock-up solenoid. 2008 Copyright by Doktor A
Great write up. This just saved me over $2000.00. 3.5 hours of labor and very easy. Thanks Dr. A.
 

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