TRANSMISSION ISSUE

SM105K

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EDIT: IT IS THE 3-5-R GEAR SET.

I just hope you aren't having the dreaded clutch steel plate/retaining clip failure on the 1-3-R drum set.
 
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DARTHSHO

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A solenoid going bad sounds right if it’s only happening In one gear wonder if the valve body doesnt have something wrong with it causing it to get stuck. Wonder what the tranny fluid pressure is during this problem. Hope they can fix it.
 

SHOdded

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I just hope you aren't having the dreaded clutch steel plate/retaining clip failure on the 1-3-R drum set.
This is what i would be most worried about, frankly, you should prepare for this as worst case scenario.

Better case scenario? Tss/Oss sensors , range sensor, and solenoid body. Which would mean no wear in internal components.

But from the volume of user experiences I have pored through, dealerships are much like old fashioned trans repair shops - all or nothing. They appear to be blissfully unaware of diagnostic procedures in the factory manual and PIDs as well.

But, as long as its on their dime, you can opt for a rebuild... As long as you get a good warranty on the job.
 

SM105K

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This is what i would be most worried about, frankly, you should prepare for this as worst case scenario.

Better case scenario? Tss/Oss sensors , range sensor, and solenoid body. Which would mean no wear in internal components.

But from the volume of user experiences I have pored through, dealerships are much like old fashioned trans repair shops - all or nothing. They appear to be blissfully unaware of diagnostic procedures in the factory manual and PIDs as well.

But, as long as its on their dime, you can opt for a rebuild... As long as you get a good warranty on the job.

I am glad you chimed in Shodded, I hope it is a simple fix for her. However, I have a feeling it isn't.
 

luigisho

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I am glad you chimed in Shodded, I hope it is a simple fix for her. However, I have a feeling it isn't.
I'm not familiar with this issue. Is this a common failure inside the transmission?

And with all the electronic monitoring this doesn't throw a failure code? or show up in a running diagnostic with them fancy diagnostic computers they have?
 

SM105K

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I'm not familiar with this issue. Is this a common failure inside the transmission?

And with all the electronic monitoring this doesn't throw a failure code? or show up in a running diagnostic with them fancy diagnostic computers they have?

Normally they won't throw the wrench code until they fail.

I also mistyped. It is the 3-5-r drum failure... Not trying to insult your intelligence however this is the easiest way to break it down.

That gear set is located in a single drum. Within the drum there are clutch material plates and "wavy"clutch steels. On the end there is a retaining clip. One of two things happens. Usually the retaining clip just literally fall off, and then everything falls out of the drum. The other thing is one of the "wavy" steel plates cracks. This creates side to side movement, which in turn makes the retaining clip literally fall off again.....

My retaining clip failed in my transmission. It made my wallet a lot lighter, and gave me Transmission PTSD.

With that being said, yes it is common failure for the 6F55 transmission. Seems the newer year SHO's have more transmissions failures from the data Shodded shared with me that he has collected.
 
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Johnbigdog

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I have been keeping tabs on this, and thinking.

The question I have, and don't know the answer to is if Daniele is having a transmission concern, or an engine performance concern. If the engine is not making power, it may extend the shifts in attempt to do what she wants (accelerate), but cant. Or is there a fault and teh transmission is defaulting to a test mode or limp home mode? A fault may or may not set a DTC if the fault does not happen long enough or enough times on a drive cycle. See if the car detects a fault, it may not set a DTC right away. It may take 2-3 times before a code sets on a drive cycle. Or the fault is detected, but because it only lasts X amount of time and the DTC threshold is Y, a DTC is not set.

Another aspect of this in relation to a lack of power. The dealership technician likely doesn't drive a SHO, or know what is normal for your car unless it is very obvious. What i feel is a lack of power, may feel like a monster to the other person driving our car. For example: The tech drives a Focus with a 1.0L and a manual transmission. He/She gets in your car, the thing probably ripps even when there may be a legitimate lack of power.

Back to the transmission concern. I cant say what you are feeling and the dealership are the same. They may be but are being described in different ways. A harsh shift could certainly feel like a "sport mode" concern and possibly be intermitent.

When it comes to a harsh shift, the PCM will not set a DTC. A harsh shift is the result of the PCM compensating for a slip. The PCM watches the Turbine Shaft Speed (input speed) and the Output shaft speed sensors and calculates the gear ratio through the transmission using these two peed sensors. The PCM also compares the calculated gear ratio to the expected programmed gear ratio. When doing this it is also counting the time it takes to reach the commanded gear ratio. If it takes to long, it will increase pressure to the clutches to see if it can resolve the "slip." The PCM does not know what a harsh shift is. All it knows is that it was programmed to get to X, Y, Z gear ratio in a certain amount of time. If that is met, the PCM is happy, but the PCM may knock your teeth out doing it.

Now, if the PCM has compensated all it can, and it still detects that it cannot reach the commanded gear ratio, a DTC will set. However this may have to occur a few times in a row on a drive cycle, it may not.

The DTC's that set will set as an informational DTC for a slip if a slip is detected. The PCM does not know if there is a mechanical solenoid, valve hydraulic pressure leak, or a burnt clutch. There could even be high resistance on an electrical circuit that the PCM cannot see that is causing a slip. I haven't come across a PCM that can measure resistance. Usually just voltage and maybe amperage.

Going back to your harsh 2-3 shift. With no DTCs, One can watch PID data to know what gear is being commanded to see that a harsh shift is felt on the 2-3 shift. The other PIDs that can be used for transmission diagnosis wont do much in this situation. The Intermediate clutch releases, the Direct clutch applies on the 2-3 shift. Most of the time a slip is a result of the applying clutch slipping. With no electrical DTCs present, the diagnostics go after a mechanical solenoid, valve in the solenoid body or main control valve body, a gasket failure in or between the main control valve body and the worm trails in the transmission, an internal hydraulic leak in the passes to the direct clutch and in the clutch support tower and Direct/Overdrive clutch hub (3,5,R), the piston, or a clutch fault (friction is steel failure).

So the next step once you know which shift is harsh is to remove the main control valve body and inspect the valves and gaskets for damage or sticking. You can test a shift solenoid electrically, but there inst really a good way to test its mechanical operation to know if its flowing the correct amount of fluid that i know of. Yes it may click, but is that a good click or a good enough click. Is it sticking when commanded to 50% who knows, so it usually gets a new one at a minimum if there isn't some other obvious faults when inspecting the main control valve body (that 800 buck part).

Since the transmission oil has been flushed so many times, your probably not going to see a lot of debris in the oil at this time and it likely wouldn't smell burnt so its difficult to say that a failing clutch would be seen or smelt.

Once you rule out the control (shift solenoid and valves) if the fault is still present you know its inside and will have to perform inspections by removing the unit. Sometimes you may not see an obvious failure though.

If the tech is savvy, he or she may be able to perform an air test to use shop air regulated down to test the various clutches. But in this test you need experience on what is good and bad. If the tech doesn't do much transmission work, the air test may be useless. One might be able to air test the direct clutch and possible see if the tone wheel moves for the direct clutch. I don't know for sure.

As for line pressure, I look at that for engagement into drive or reverse. There are no specifications for forward gear pressures. There is a line pressure control solenoid that feeds the individual shift solenoids. the individual shift solenoids then control the clutches. So you may not see a line pressure fault. There inst pressure ports for all the individual clutches nor specs on what is good.

I recall the TSB for the snap ring failure was for specific model years, but I don't recall what model years.

PID data diagnosis heavily depends on if the tech knows what PIDs to look at, what to expect and is good/bad. The publications doesn't cover EVERYTHING unfortunately.

That's just a little bit. If it comes down to a lack of power, I dont know. there is a log of things.
 

luigisho

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That's what I was looking for. I had the same confusion engine not performing or transmission issue. I was hoping some of the operating parameters would flag something to at least look at.
 

luigisho

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EDIT: IT IS THE 3-5-R GEAR SET.

I just hope you aren't having the dreaded clutch steel plate/retaining clip failure on the 1-3-R drum set.
Is that confirmed? All caps sounds like
You must be registered for see images
 

Zpak

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I have been keeping tabs on this, and thinking.

The question I have, and don't know the answer to is if Daniele is having a transmission concern, or an engine performance concern. If the engine is not making power, it may extend the shifts in attempt to do what she wants (accelerate), but cant. Or is there a fault and teh transmission is defaulting to a test mode or limp home mode? A fault may or may not set a DTC if the fault does not happen long enough or enough times on a drive cycle. See if the car detects a fault, it may not set a DTC right away. It may take 2-3 times before a code sets on a drive cycle. Or the fault is detected, but because it only lasts X amount of time and the DTC threshold is Y, a DTC is not set.

Another aspect of this in relation to a lack of power. The dealership technician likely doesn't drive a SHO, or know what is normal for your car unless it is very obvious. What i feel is a lack of power, may feel like a monster to the other person driving our car. For example: The tech drives a Focus with a 1.0L and a manual transmission. He/She gets in your car, the thing probably ripps even when there may be a legitimate lack of power.

Back to the transmission concern. I cant say what you are feeling and the dealership are the same. They may be but are being described in different ways. A harsh shift could certainly feel like a "sport mode" concern and possibly be intermitent.

When it comes to a harsh shift, the PCM will not set a DTC. A harsh shift is the result of the PCM compensating for a slip. The PCM watches the Turbine Shaft Speed (input speed) and the Output shaft speed sensors and calculates the gear ratio through the transmission using these two peed sensors. The PCM also compares the calculated gear ratio to the expected programmed gear ratio. When doing this it is also counting the time it takes to reach the commanded gear ratio. If it takes to long, it will increase pressure to the clutches to see if it can resolve the "slip." The PCM does not know what a harsh shift is. All it knows is that it was programmed to get to X, Y, Z gear ratio in a certain amount of time. If that is met, the PCM is happy, but the PCM may knock your teeth out doing it.

Now, if the PCM has compensated all it can, and it still detects that it cannot reach the commanded gear ratio, a DTC will set. However this may have to occur a few times in a row on a drive cycle, it may not.

The DTC's that set will set as an informational DTC for a slip if a slip is detected. The PCM does not know if there is a mechanical solenoid, valve hydraulic pressure leak, or a burnt clutch. There could even be high resistance on an electrical circuit that the PCM cannot see that is causing a slip. I haven't come across a PCM that can measure resistance. Usually just voltage and maybe amperage.

Going back to your harsh 2-3 shift. With no DTCs, One can watch PID data to know what gear is being commanded to see that a harsh shift is felt on the 2-3 shift. The other PIDs that can be used for transmission diagnosis wont do much in this situation. The Intermediate clutch releases, the Direct clutch applies on the 2-3 shift. Most of the time a slip is a result of the applying clutch slipping. With no electrical DTCs present, the diagnostics go after a mechanical solenoid, valve in the solenoid body or main control valve body, a gasket failure in or between the main control valve body and the worm trails in the transmission, an internal hydraulic leak in the passes to the direct clutch and in the clutch support tower and Direct/Overdrive clutch hub (3,5,R), the piston, or a clutch fault (friction is steel failure).

So the next step once you know which shift is harsh is to remove the main control valve body and inspect the valves and gaskets for damage or sticking. You can test a shift solenoid electrically, but there inst really a good way to test its mechanical operation to know if its flowing the correct amount of fluid that i know of. Yes it may click, but is that a good click or a good enough click. Is it sticking when commanded to 50% who knows, so it usually gets a new one at a minimum if there isn't some other obvious faults when inspecting the main control valve body (that 800 buck part).

Since the transmission oil has been flushed so many times, your probably not going to see a lot of debris in the oil at this time and it likely wouldn't smell burnt so its difficult to say that a failing clutch would be seen or smelt.

Once you rule out the control (shift solenoid and valves) if the fault is still present you know its inside and will have to perform inspections by removing the unit. Sometimes you may not see an obvious failure though.

If the tech is savvy, he or she may be able to perform an air test to use shop air regulated down to test the various clutches. But in this test you need experience on what is good and bad. If the tech doesn't do much transmission work, the air test may be useless. One might be able to air test the direct clutch and possible see if the tone wheel moves for the direct clutch. I don't know for sure.

As for line pressure, I look at that for engagement into drive or reverse. There are no specifications for forward gear pressures. There is a line pressure control solenoid that feeds the individual shift solenoids. the individual shift solenoids then control the clutches. So you may not see a line pressure fault. There inst pressure ports for all the individual clutches nor specs on what is good.

I recall the TSB for the snap ring failure was for specific model years, but I don't recall what model years.

PID data diagnosis heavily depends on if the tech knows what PIDs to look at, what to expect and is good/bad. The publications doesn't cover EVERYTHING unfortunately.

That's just a little bit. If it comes down to a lack of power, I dont know. there is a log of things.
Nice, now that’s cracking an egg of knowledge.
 

SM105K

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No, not necessarily. It can cause the tone ring for the t.s.s. to move out of the way of the sensor just long enought for the transmission to default into limp home mode or confuse the pcm.
Or when you turn a hard left and all of a sudden you have third gear until it shift into 4th....happened to me on the way to the trans shop. I was like WTF?
 

Johnbigdog

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Or when you turn a hard left and all of a sudden you have third gear until it shift into 4th....happened to me on the way to the trans shop. I was like WTF?

In fair point, I recall some wierd problems before that you reported tooo. It wasnt a student and abrupt failure.
 

SM105K

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In fair point, I recall some wierd problems before that you reported tooo. It wasnt a student and abrupt failure.
My whole trans failure was quite the adventure to say the least.
 

DGrot777

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Your car sounds pretty similar to how mine was kept up. The sunroof seal doesn't leak but it's worn, my trunk has a rust spot developing, front bumper was definitely poorly repainted (didn't see the white didn't match when I bought it) and I think my trans is going as well. My car did the same thing where it would hold RPM in drive, only difference between you and me is mine shakes sometimes. Feels like it's on rumble strips. Not sure if it's my steel police wheels (they don't feel balanced at higher speeds) but when I went for a transmission drain and refill it shifted a lot better and wouldn't hold as long. Hopefully your dealer figures it out. Curious what's going on, maybe it'll help me out.
 
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