[zroger73]

Ok, so I just called Honda corporate and gave them the VIN of my Accord and Ridgeline and they say that the service bulletin does not cover my vehicles. I know that the service bulletin for the Accord has the word ALL printed in the Vin Range box. Now I am really confused. The lady at corporate know her stuff so I don't think there is any misunderstanding here. Initially I thought that maybe she only know about recalls and not service bulletins. There must be more to this.

Don't forget the TSBs and Tech Line articles are "technical information to dealers" - they aren't mandatory safety recalls. TSBs are typically only performed if the customer experiences the issue described in the bulletin and the dealer can reproduce it. Dealers typically don't perform TSBs as a proactive measure just because a customer becomes aware of the bulletin and wants to nip something in the bud.

 

[JJ13]

Appreciate the links! And yeah, I am guilty of blaming VCM as well, but there is a very discernible shudder noise coming from the engine bay, and I cant quite get it to do it on command, but maybe this is the source of the problem. The TSB states that the judder can be felt, however it doesn't mention that it is audible as well? I don't feel it in the wheel when I'm driving its only a shudder noise that lasts maybe 1-2 seconds.

http://www.filedropper.com/17-025
http://www.filedropper.com/17-026



I find it interesting how some people swear that VCM is causing all sorts of prominent noises and vibrations while others can barely tell when it transitions. Admittedly, I have to focus intently to determine when it's running on 3-cylinders. Had I not known the vehicle had VCM, I'd never notice. It does make me wonder if they could actually be experiencing TC clutch judder instead.

 

[14v6]

http://www.filedropper.com/17-025
http://www.filedropper.com/17-026



I find it interesting how some people swear that VCM is causing all sorts of prominent noises and vibrations while others can barely tell when it transitions. Admittedly, I have to focus intently to determine when it's running on 3-cylinders. Had I not known the vehicle had VCM, I'd never notice. It does make me wonder if they could actually be experiencing TC clutch judder instead.

On the Accord I feel something, it's subtle. I don't know if it is the torque converter or the VCM but on the RL, it is even more subtle, you have to really look for it. One thing I can say is that the Accord uses no oil, have never had to add and I go 5k-6 k between changes. However, when you floor it and look at the rear view mirror, I definitely see black smoke, go figure. On the Accord and RL, it did go down on the stick a little on the break in oil. I wll do the first oil change on the RL soon. Currently at 5300 and 30%.

 

[Jeffrob]

I only have ~2900 miles on my RTL, but the VCM transition feels more like a hesitation and vibration to me. Having to press harder on the accelerator, then slight vibration.
I have a 2014 Camry that had a torque converter judder which felt more like a quick slipping and catching, over and over again.
The ECU was reprogrammed and the converter replaced to solve that problem.

 

[14v6]

Don't forget the TSBs and Tech Line articles are "technical information to dealers" - they aren't mandatory safety recalls. TSBs are typically only performed if the customer experiences the issue described in the bulletin and the dealer can reproduce it. Dealers typically don't perform TSBs as a proactive measure just because a customer becomes aware of the bulletin and wants to nip something in the bud.

Yes, well put, but I learned that when I called Honda, I have a battery monitor service bulletin on the Accord and I will be notified when parts become available but it is not a recall even though there is a risk of fire:surprise: Honda rarely does stuff for free unless there is a safety issue (recall) or your car has a problem and they can start replacing stuff for free as part of a service bulletin. I have had this done for valve cover gaskets twice. Furthermore, most folks are clueless. I wouldn't know if I experienced judder or normal operation. This judder recall is different though because it is based on how hard you use your truck to degrade the fluid to create a judder before the mm says to change the fluid. I don't understand why they don't take a one size fits all approach and at least check the history to see if the truck experienced a judder.

Oh well, time to buy some more DW-1.:frown:

 

[Jeffrob]

Most of the heat in a transmission is generated by the friction of the fluid in the torque converter. Less heat is generated during partial engagement of the torque converter clutch. Some heat is generated by the clutches during gear changes.

There are two ways I know of to manage heat through software. One is to increase the speed of shifts which will reduce the amount of slippage of the clutches in between shifts. The other is to increase the use and engagement speed of the torque converter clutch. Both methods will decrease the amount of heat generated at the expense of shift comfort since shifts and TCC engagement will be harsher. The degree of harshness depends on how much adjustment is made.

It's unknown at this time whether the software update is intended to compensate for an inherent design flaw with the transmission or if it simply corrects a software issue that causes the transmission to overheat and burn the fluid.

Personally, I'd suggest having this TSB performed ASAP and would change my transmission fluid more frequently until or unless more is known about this issue.

zroger73

What do you mean about partial engagement of torque converter clutch. Are you referring to the lock up clutch, or the torque converter itself?

 

[zroger73]

What do you mean about partial engagement of torque converter clutch. Are you referring to the lock up clutch, or the torque converter itself?

A TCC (torque converter clutch) can be fully released, fully applied, or anywhere in between. The amount of application is determined by the design of the transmission, line pressure, and PWM (pulse width modulated) solenoids controlled by a computer. This allows the TCC to be smoothly applied for comfort. The amount of slip is regulated by the computer and varies by condition.

 

[Jeffrob]

A TCC (torque converter clutch) can be fully released, fully applied, or anywhere in between. The amount of application is determined by the design of the transmission, line pressure, and PWM (pulse width modulated) solenoids controlled by a computer. This allows the TCC to be smoothly applied for comfort. The amount of slip is regulated by the computer and varies by condition.

Isn't the least heat generated when locked?

 

[Jeffrob]

A TCC (torque converter clutch) can be fully released, fully applied, or anywhere in between. The amount of application is determined by the design of the transmission, line pressure, and PWM (pulse width modulated) solenoids controlled by a computer. This allows the TCC to be smoothly applied for comfort. The amount of slip is regulated by the computer and varies by condition.

Isn't the purpose of the TCC torque converter clutch to eliminate the fluid coupling and replace it with a direct ~ 1:1 drive?
I understand the smoothly applied comment. We used to change springs in valve bodies of transmissions in the 70's and 80's
to get quicker shifts resulting in much harder shifts for some ET racing and street use. These were differently designed planetary drive transmissions but the torque converters were much the same.

 

[zroger73]

Isn't the least heat generated when locked?

Yes.

Isn't the purpose of the TCC torque converter clutch to eliminate the fluid coupling and replace it with a direct ~ 1:1 drive?

Yes.

The torque converter clutch judder is caused by "deteriorated" fluid.

Deteriorated fluid is caused by overheating.

Overheating results when the the transmission generates more heat than can be dissipated by heat exchanger

Heat is generated primarily from (1) torque converter slip, (2) torque converter clutch slip, and/or (3) gear clutch slip.

All three of these conditions are monitored closely by the computer and if they exceed programmed limits a DTC(s) will set indicating excess slip and/or incorrect gear ratio.

 

[Jeffrob]

Yes.



Yes.

The torque converter clutch judder is caused by "deteriorated" fluid.

Deteriorated fluid is caused by overheating.

Overheating results when the the transmission generates more heat than can be dissipated by heat exchanger

Heat is generated primarily from (1) torque converter slip, (2) torque converter clutch slip, and/or (3) gear clutch slip.

All three of these conditions are monitored closely by the computer and if they exceed programmed limits a DTC(s) will set indicating excess slip and/or incorrect gear ratio.

Right, Honda is saying this torque converter judder is caused by deteriorated fluid because of excessive high temperature operation.
The judder is the torque converter clutch trying to lock up, but unable to do so because of perhaps a viscosity or additive problem?
Isn't most transmission fluid heat caused by the torque converter operation (slippage)?
Do you think the extra unlocking and locking of the TCC during VCM operation of around town 35+ MPH cruising and highway cruising could contribute to the excessive high temperature operation? The extra time unlocked could raise temperatures.
I don't know, what do you think?

 

[zroger73]

Right, Honda is saying this torque converter judder is caused by deteriorated fluid because of excessive high temperature operation.
The judder is the torque converter clutch trying to lock up, but unable to do so because of perhaps a viscosity or additive problem?
Isn't most transmission fluid heat caused by the torque converter operation (slippage)?
Do you think the extra unlocking and locking of the TCC during VCM operation of around town 35+ MPH cruising and highway cruising could contribute to the excessive high temperature operation? The extra time unlocked could raise temperatures.
I don't know, what do you think?

The TSB states, "The judder is caused by deteriorated transmission fluid." "Deteriorated" is a nice way of saying "burnt". I do not believe the judder is the cause of the overheating and burnt fluid, but rather the result of the overheating and burnt fluid.

Yes - most heat is caused by fluid shear in the torque converter. In order to minimize heat, you'd want to keep the torque converter clutch fully applied as often as possible (which would be any time the vehicle was moving fast enough in the applied gear to prevent the engine from falling below idle speed), but this negates the torque multiplication function of the torque converter and would cause rough operation.

The action of applying and releasing of the torque converter clutch itself generates minimal heat. The heat generated due to the friction that occurs during partial application of the torque converter clutch doesn't last long and is minimal. The transmission can easily dissipate this small a mount of heat quickly.

Gear clutches only slip for a split second and generate minimal heat only during gear changes.

The torque converter clutch and/or gear clutches would have to slip for long periods under heavy loads to generate heat faster than it could be dissipated. If this happened, there should be some obvious driveability issues and/or warning lights.

The logical conclusion is that the torque converter is the culprit generating the extra heat.

 

[Jeffrob]

The TSB states, "The judder is caused by deteriorated transmission fluid." "Deteriorated" is a nice way of saying "burnt". I do not believe the judder is the cause of the overheating and burnt fluid, but rather the result of the overheating and burnt fluid.

Yes - most heat is caused by fluid shear in the torque converter. In order to minimize heat, you'd want to keep the torque converter clutch fully applied as often as possible (which would be any time the vehicle was moving fast enough in the applied gear to prevent the engine from falling below idle speed), but this negates the torque multiplication function of the torque converter and would cause rough operation.

The action of applying and releasing of the torque converter clutch itself generates minimal heat. The heat generated due to the friction that occurs during partial application of the torque converter clutch doesn't last long and is minimal. The transmission can easily dissipate this small a mount of heat quickly.

Gear clutches only slip for a split second and generate minimal heat only during gear changes.

The torque converter clutch and/or gear clutches would have to slip for long periods under heavy loads to generate heat faster than it could be dissipated. If this happened, there should be some obvious driveability issues and/or warning lights.

The logical conclusion is that the torque converter is the culprit generating the extra heat.

So more time unlocked or unapplied for the torque converter clutch means more heat.

Do you think the extra time unlocked during VCM could help raise these temperatures to the excessive range?

These Honda and other newer transmissions seem to be engineered so that very minor differences in fluid levels and fluid properties can cause major problems.

The Camry transmission I referred to above does not have a dipstick, and fluid level can only be checked at a very specific temperature by removing the fill plug like a differential and checking. It's approximately a 1 hour labor charge after a specific cool down and warm up procedure. ~$75-100 to check your transmission fluid level. Great eh! One of the reasons I bought a Honda. With a dipstick.

 

[Jeffrob]

zroger73
Do you or does anyone else know if you can monitor transmission temp with one of the ELM327 bluetooth devices.
I have an older Scanguage and have many options but not Transmission temp.

 

[longboat]

...
I understand the smoothly applied comment. We used to change springs in valve bodies of transmissions in the 70's and 80's
to get quicker shifts resulting in much harder shifts for some ET racing and street use. These were differently designed planetary drive transmissions but the torque converters were much the same.

Those shift kits did make the trannies shift a lot harder. Perhaps surprisingly, that was good for the transmission (but perhaps very bad for the rest of the driveline downstream of the trans). In fact, that was part of a recommended fix for Dodge trucks in the late 80s/early 90s when they started having tranny failures behind the Cummins. Adding a shift kit was a key part of preventative maintenance to keep the tranny from failing, as well as adjusting valving to allow more fluid flow at lower rpms where the diesels delivered their torque.

I would think one could tap into the trans lines and add an additional cooler. Ideally, there should be a valve going to that extra cooler that only opens when a certain fluid temp is reached, like a thermostat on a radiator. That could go a LONG way toward keeping the fluid from being burnt, but still allowing the trans to get to operati g temp quickly.

I'm hoping that when the G3 comes equipped with the 13-spd DCT (or us it a TCT?), these archaic worries will be behind us. If that's not going to happen, at least give us a 6-spd manual. Are you listening Honda?

 

[zroger73]

So more time unlocked or unapplied for the torque converter clutch means more heat.

Do you think the extra time unlocked during VCM could help raise these temperatures to the excessive range?

The Camry transmission I referred to above does not have a dipstick, and fluid level can only be checked at a very specific temperature by removing the fill plug like a differential and checking. It's approximately a 1 hour labor charge after a specific cool down and warm up procedure. ~$75-100 to check your transmission fluid level. Great eh! One of the reasons I bought a Honda. With a dipstick.

Yes - the more time the torque converter clutch spends less than fully applied and the more power produced by the engine, the more heat is produced.

I think it's safe to say that the TCC is only released momentary during the transition into or out of 3-cylinder mode. Leaving the TCC unapplied or partially applied in 3-cylinder mode would offset the fuel economy gains of running in 3-cylinder mode.

I'm used to "sealed for life" automatic transmissions having been first exposed to them in mid-90s GM vehicles.

 

[14v6]

The TSB states, "The judder is caused by deteriorated transmission fluid." "Deteriorated" is a nice way of saying "burnt". I do not believe the judder is the cause of the overheating and burnt fluid, but rather the result of the overheating and burnt fluid.

Yes - most heat is caused by fluid shear in the torque converter. In order to minimize heat, you'd want to keep the torque converter clutch fully applied as often as possible (which would be any time the vehicle was moving fast enough in the applied gear to prevent the engine from falling below idle speed), but this negates the torque multiplication function of the torque converter and would cause rough operation.

The action of applying and releasing of the torque converter clutch itself generates minimal heat. The heat generated due to the friction that occurs during partial application of the torque converter clutch doesn't last long and is minimal. The transmission can easily dissipate this small a mount of heat quickly.

Gear clutches only slip for a split second and generate minimal heat only during gear changes.

The torque converter clutch and/or gear clutches would have to slip for long periods under heavy loads to generate heat faster than it could be dissipated. If this happened, there should be some obvious driveability issues and/or warning lights.

The logical conclusion is that the torque converter is the culprit generating the extra heat.

So what does the reprogramming actually do? It has to come at the expense of something, there is no free lunch. My guess is that it would hurt drivetrain feel or mpg's. I wouldn't mind if the reprogramming caused less VCM operation. If all these theories are correct, changing the Dw-1 more frequently seems like cheap insurance. I remember years ago, the rear diffs on CRV's were making noise within their recommended change interval. Solution, change the fluid more often.

 

[BillmanMotion]

16k miles, including a 2000 mile round trip towing the car trailer through the mountains, and the trans has been fantastic.

Have not changed the fluid yet, but hoping to this weekend.

The drain plug should be magnetic, will report on fluid condition and magnet collection.

Takes 3.3 quarts, simple drain and fill.

 

[longboat]

My guess is that re-programming would cause harder shifts, or rather, more abrupt shifts. If they do it right, it will only happen when the trans fluid gets above X degrees. Knowing Honda, it will be an algorithm involving rate of temp increase, ambient temp, elevation, etc.

They won't mess with VCM, as that will affect their MPG ratings and get them in hot water with EPA.

 

[Jeffrob]

Yes - the more time the torque converter clutch spends less than fully applied and the more power produced by the engine, the more heat is produced.

I think it's safe to say that the TCC is only released momentary during the transition into or out of 3-cylinder mode. Leaving the TCC unapplied or partially applied in 3-cylinder mode would offset the fuel economy gains of running in 3-cylinder mode.

I'm used to "sealed for life" automatic transmissions having been first exposed to them in mid-90s GM vehicles.

I've always liked that term "Sealed for Life" It means what it says.