Transmission Update
Race Director
Joined: Aug 2019
Posts: 12,351
Likes: 14,185
From: Central Illinois
Quite possible one of the codes they see on the car indicates a known problem that flushing won't correct?
For instance, there is a known issue with the seals on the rails that the shift forks ride on that cause misalignment if they aren't installed properly in the factory.
If they see a code related to that, then a flush isn't going to correct that issue.
For instance, there is a known issue with the seals on the rails that the shift forks ride on that cause misalignment if they aren't installed properly in the factory.
If they see a code related to that, then a flush isn't going to correct that issue.
Melting Slicks
Joined: May 2021
Posts: 2,562
Likes: 1,579
Maybe we can dig up more details online or here on the forum? I didn't just "imagine" the seal/alignment issue. It was related by someone that works on these transmissions. I wonder if the shop manual has a teardown / break out diagram of all the DCT components? Would be interesting to see what "seal" they could possible be talking about.
This isn't related to the pan seal, this was specifically mentioned that it some how would be mis-aligned when the back end of the DCT was being assembled. I suppose a very slight misalignment could cause things to bind under certain circumstances.
This isn't related to the pan seal, this was specifically mentioned that it some how would be mis-aligned when the back end of the DCT was being assembled. I suppose a very slight misalignment could cause things to bind under certain circumstances.
Thread Starter
Burning Brakes
Joined: Mar 2011
Posts: 1,208
Likes: 320
From: “Out there”
OP here. Two days ago, I started the car after being on the battery maintainer over night. Got odd and even gears. Will try again later today and report back. And it is cold (Wisconsin).
So, just spitballing here, but maybe there is debris, or gunk (or a McDonalds wrapper), on the shift rods, or misalignment, or stiction, making it a bit harder to activate the shift forks, or rails, rods, whatever’s all in there. So when the battery may not be 100%, there is not enough “oomph” to activate the forks, rods, whatever. But after sitting on the charger, the battery has enough power to force the rods to move, and once moved, they stay unstuck, until the car sits, battery is less than ideal, and they get stuck again. It kinda’ makes sense, since the times I lost the odd gears, If I drove a few miles, I would get all the gears. So maybe the car charged the battery enough to move the forks. And once moved, worked properly. Or it is temperature related and once a certain degree was reached, it once again shifted properly. But I’m leaning on the theory that there is gunk (debris) on the forks, and it takes all the batterie’s power to get it moving. But, what the hell do I know?
So, just spitballing here, but maybe there is debris, or gunk (or a McDonalds wrapper), on the shift rods, or misalignment, or stiction, making it a bit harder to activate the shift forks, or rails, rods, whatever’s all in there. So when the battery may not be 100%, there is not enough “oomph” to activate the forks, rods, whatever. But after sitting on the charger, the battery has enough power to force the rods to move, and once moved, they stay unstuck, until the car sits, battery is less than ideal, and they get stuck again. It kinda’ makes sense, since the times I lost the odd gears, If I drove a few miles, I would get all the gears. So maybe the car charged the battery enough to move the forks. And once moved, worked properly. Or it is temperature related and once a certain degree was reached, it once again shifted properly. But I’m leaning on the theory that there is gunk (debris) on the forks, and it takes all the batterie’s power to get it moving. But, what the hell do I know?
Melting Slicks
Joined: May 2021
Posts: 2,562
Likes: 1,579
OP here. Two days ago, I started the car after being on the battery maintainer over night. Got odd and even gears. Will try again later today and report back. And it is cold (Wisconsin).
So, just spitballing here, but maybe there is debris, or gunk (or a McDonalds wrapper), on the shift rods, or misalignment, or stiction, making it a bit harder to activate the shift forks, or rails, rods, whatever’s all in there. So when the battery may not be 100%, there is not enough “oomph” to activate the forks, rods, whatever. But after sitting on the charger, the battery has enough power to force the rods to move, and once moved, they stay unstuck, until the car sits, battery is less than ideal, and they get stuck again. It kinda’ makes sense, since the times I lost the odd gears, If I drove a few miles, I would get all the gears. So maybe the car charged the battery enough to move the forks. And once moved, worked properly. Or it is temperature related and once a certain degree was reached, it once again shifted properly. But I’m leaning on the theory that there is gunk (debris) on the forks, and it takes all the batterie’s power to get it moving. But, what the hell do I know?
So, just spitballing here, but maybe there is debris, or gunk (or a McDonalds wrapper), on the shift rods, or misalignment, or stiction, making it a bit harder to activate the shift forks, or rails, rods, whatever’s all in there. So when the battery may not be 100%, there is not enough “oomph” to activate the forks, rods, whatever. But after sitting on the charger, the battery has enough power to force the rods to move, and once moved, they stay unstuck, until the car sits, battery is less than ideal, and they get stuck again. It kinda’ makes sense, since the times I lost the odd gears, If I drove a few miles, I would get all the gears. So maybe the car charged the battery enough to move the forks. And once moved, worked properly. Or it is temperature related and once a certain degree was reached, it once again shifted properly. But I’m leaning on the theory that there is gunk (debris) on the forks, and it takes all the batterie’s power to get it moving. But, what the hell do I know?
Thread Starter
Burning Brakes
Joined: Mar 2011
Posts: 1,208
Likes: 320
From: “Out there”
Yeah, that's not how it works unfortunately. The oomph all comes from hydraulics. That is why engine needs to be running to shift gears. It's a mechanical pump. Solenoids control the flow though. Not sure how much current those require, but my guess is the battery (especially once engine is running) has more than enough power to move them.
So the solenoids are activated by electrical current? Then the solenoids move the hydraulic fluid to work the transmission?
Inquiring minds need to know. Thanks in advance.
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Melting Slicks
Joined: May 2021
Posts: 2,562
Likes: 1,579
It's probably these rods in the solenoids that are sticking due to debris.
Thread Starter
Burning Brakes
Joined: Mar 2011
Posts: 1,208
Likes: 320
From: “Out there”
Yeah, that's not how it works unfortunately. The oomph all comes from hydraulics. That is why engine needs to be running to shift gears. It's a mechanical pump. Solenoids control the flow though. Not sure how much current those require, but my guess is the battery (especially once engine is running) has more than enough power to move them.
A solenoid is an electromagnetic coil that moves a rod in the center. The rods are connected to valves which control the flow of hydraulic fluid. The fluid pressure moves pistons, actuators, etc..
It's probably these rods in the solenoids that are sticking due to debris.
It's probably these rods in the solenoids that are sticking due to debris.
Melting Slicks
Joined: Sep 2009
Posts: 2,028
Likes: 357
I'd like to know this as well. I imagine that since the pan has to be dropped to get to the valve body, they would have to refill with new fluid. Do they replace the filter(s) (one or both)?
Race Director
Joined: Aug 2016
Posts: 12,812
Likes: 10,229
From: Garden Valley CA
I think the valve body is on the side of the transmission, I don't think they need to drop the pan to access it.
Thread Starter
Burning Brakes
Joined: Mar 2011
Posts: 1,208
Likes: 320
From: “Out there”
OP here. Took car in to dealership around Christmas because my transmission was only using even gears. No flush, tech said needed a new TCM. Service person recently stated he is still waiting for the valve body to arrive. Question: are the two the same thing? And nothing has arrived yet?
Race Director
Joined: Aug 2019
Posts: 12,351
Likes: 14,185
From: Central Illinois
OP here. Took car in to dealership around Christmas because my transmission was only using even gears. No flush, tech said needed a new TCM. Service person recently stated he is still waiting for the valve body to arrive. Question: are the two the same thing? And nothing has arrived yet?
Thread Starter
Burning Brakes
Joined: Mar 2011
Posts: 1,208
Likes: 320
From: “Out there”
So the TCM controls the valve body. They are to replace the valve body only, I assume. Any debris or stiction has to do with the valve body. Also l assume, the TCM is fine, and needn’t be replaced. Thanks.
Advanced
Joined: Jun 2007
Posts: 59
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From: Long Island , NY
I can not believe everyone complains about people complaining !!! ??? Get it !! You guys are complaining !! If you do not like thread .....MOVE on to another !!! Human nature !!! Everyone complains !!! Get over it !!!!
Safety Car
Joined: Dec 1999
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From: Virginia Beach, VA & Port Charlotte, FL
I'd like to take this opportunity to complain about your complaining about people complaining about other people's complaining.
