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Ok, guys, with several members having transmissions with problems at higher mileage, I'm considering the following:

When I do winter maintainance this year, I think I'll try to do the Nissan caps on the transmission shift pistons.

This is an INTERNAL Nissan improvement, and obviously holds some merit.

With price not an issue, I'd consider the Dodson pistons, but are obviously a heavy duty solution.

WillAll's shift "stoppers" are also interesting, but I'm not sure I'm up to that task. Nissan's cautions about "cleaning" the shift pistons are also quite ominous, and give me pause, for both the Dodson and WillAll solutions to this problem.

The mechanical wherewithall it requires to install the shift "caps" from Nissan doesn't intimidate me AT ALL. I've had that pan and filter off before, and the valve body with allen bolts also does not look difficult.

Here's my problem and thoughts:

I'm told the car goes into "limp" mode when the valve body is removed and requires reset. Nissan's TSB doesn't mention this, but does say a "clutch relearn" must be done prior to test driving the car. If I end up in "non-movable mode" in my garage, towing to Nissan will be difficult, and expensive.

I can get access to a Cobb, but didn't want anything to access my ECU other than the dealers Consult III because of warranty issues. I'm in a very grey area because of my fluid choices. Also, concurrent to this considered upgrade, I'm upgrading the transmission pan with the new baffles to the 2012 pan. I have it my garage. Since I'm going to have that pan off anyway, I see this as a doable upgrade, but with this "limp mode" concern, I'm a little worried.

Any help? Any special way to avoid the "limp mode?" Will disconnecting the battery prior to removing the valve body "fool" the ECU into not knowing the valve body was removed? Can I just borrow my buddies Cobb and hit the "relearn" function and be okay, or can I "limp" to Nissan with the clutch out of adjustment and be okay. Frankly, I don't see how these caps change the clutch engagement or touch points, but that may be due to not understanding how the caps change how the pistons engage the forks. I'm willing to listen and learn. Dodson's guys suggested I leave it to an experienced shop, but all of those are minimum four hour drives from where I live.

Shawn
 

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If I were you, I think the best solution is to borrow your bud's AP NIS-006 after he uninstalls it, do the relearn on your after installing it, then go back and uninstall it from yours and reinstall it in his. This is how Shep adjusted TPs and CCs when he had mine in for work.
 

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CMD
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Shawn,

Another idea that maybe the AP gurus out there can comment on. During the uninstall/install, the AP will flash twice... one for the TCM and one for the ECU (maps). (Just found this out myself last night as I did both of these for the first time with the alpha firmware+LC4 map install.) I wonder if there is someway where you only flash the TCM portion, which would give you gear re-learn and touch point correction capability but not mess with the ECU?

I'm also interested in these "caps"... to me, it sounds like a Nissan design shortcoming, but for some reason, it's not being sent out as a fix. Apparently, the process to document this issue and implement the fix at Nissan is quite tricky as well... your tech will have to do screen captures during the diag, send it to Nissan NA, and only then would they consider apply this TSB. Complete nonsense if you ask me.
 

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If it is not in the TSB I am going to assume you would not need to do a reset for removing the valve body. I am not a GT-R tech but I can check in our Consult III Plus and see. Also food for thought. If you have the battery disconnected from the car so there is no power through any systems, how would the car ever know you removed and replaced the same identical valve body ;) I am going to venture and say you only need to do a relearn.
 

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WillAll's shift "stoppers" are also interesting, but I'm not sure I'm up to that task. Nissan's cautions about "cleaning" the shift pistons are also quite ominous, and give me pause, for both the Dodson and WillAll solutions to this problem.
What are Nissans cautions as per the shift pistons, I for one would be interested to hear them?
Nissan are full of interesting comments, such as its good that the GTR is so heavy, thats why it handles well....
 

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I can get access to a Cobb, but didn't want anything to access my ECU other than the dealers Consult III because of warranty issues. I'm in a very grey area because of my fluid choices. Also, concurrent to this considered upgrade, I'm upgrading the transmission pan with the new baffles to the 2012 pan. I have it my garage. Since I'm going to have that pan off anyway, I see this as a doable upgrade, but with this "limp mode" concern, I'm a little worried.
If you're really concerned about warranty, any use of the cobb that requires a flash means you're done. There is no way for Nissan to tell the difference between you "just flashed it so I could get it out of limp mode" and flashing it and running it hard all the time.

In other words, in for a penny, in for a pound. If you use the cobb to relearn, any serious warranty claim is going to involve Nissan considering you "guilty" of modding the car, and they're very unlikely to just take your word for it on how it was used.
 

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Discussion Starter · #9 ·

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Discussion Starter · #10 ·
If it is not in the TSB I am going to assume you would not need to do a reset for removing the valve body. I am not a GT-R tech but I can check in our Consult III Plus and see. Also food for thought. If you have the battery disconnected from the car so there is no power through any systems, how would the car ever know you removed and replaced the same identical valve body ;) I am going to venture and say you only need to do a relearn.
Page 11 of TSB only says relearn, but it stresses, BEFORE TEST DRIVING.

http://www.nagtroc.org/forums/index.php?/topic/25571-nissan-gt-r-technical-service-bulletin-recall-database/page__view__findpost__p__734042

Shwn
 

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COBB Tuning Firmware Engineer (Hacker)
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FYI. the AccessPORT doesn't have to be installed on your TCM to do touch point adjustment or gear learning. As long as the AccessPORT is installed on someone's ECU and it's a AP-NIS-006 you'll be able to gear learning and touch point adjustment on any GT-R minus the 2012. I'm still working on the LC4 tp and clutch learning.

Joe
 

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What are Nissans cautions as per the shift pistons, I for one would be interested to hear them?
From page 8 of the TSB:

Set the ACM in a clean working area.

CAUTION:
• Do Not use fabric gloves.
• Use only lint free rags.
Do NOT clean debris off of the pistons.
Any wiping or cleaning of the pistons will scratch the piston coating.
Do not wipe, touch, or in anyway clean the debris off of the pistons.

Seriously? Are the pistons really that fragile? Can anyone with who has installed the Willall Gear Stoppers comment?
 

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There is another recent thread talking about the coating on the shift pistons easily scratches and comes off. Sounds like this TSB should have included new pistons with a better coating.
 

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Hey Shawn what's the part number for the nissan shift caps?
I'd like to install them myself too.
 
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