GX460 P2714 P0761 Ultimate Summary and Hope For A Fix Thread

[re_guderian]

It isn't year of make as much as miles on the tranny. Like @StriderWolf said some as low as 80K. 120K-180K seem the most common and in reality that is a lot of miles don't care who makes it. Facebook GX 460 group and Club Lexus have a lot of traffic and most don't tow or even see dirt, and have no mods they are kid haulers and grocery getters. The common theme with those failing seems to be living in the deep South where it gets very hot in the summer. With a disproportionately large number of them being in Florida and Texas.

Another common theme is I haven't seen anyone that added an external tranny cooler or do a simple drain and fill every 60K have any tranny issues. Personally I would not do a tranny flush especially with 79K on it but I would add a cooler and do a drain and fill while you're at it. Especially living in Texas. Might as well drop the pan and replace the filter while at it but it isn't much of a filter. I'm not going to drop the pan on mine for the next drain and fill which will happen every 30K from now on.

Thanks for reporting back to us as I am not sure someone has done all the pre items, solenoids AND the valve body. Hope it works for you!

Side note… Reading above, I had not heard the theory on GXs in the south having more issues with this. That’s new to me! Interesting as we bought one from TX with great records, service, etc. It appears the ATF wasn’t changed until after 100k, but it fits the mold of a southern vehicle.

I'd be leery of the TX/FL deep south connection. TX and FL are two of the to four most populous states, and have known high concentrations of GX's. They're likely to have higher amounts of everything GX-related, but not necessarily higher RATES of failures...

 

[Rusty Marlin]

Test drive update.

I didn't kill it.
Rig is all back together and shifts buttery smooth.
But this was with a "hot" test after setting the fluid level per the FSM.
We'll see how it acts with cold starts in the coming weeks.

 

[FloydtheQPilot]

I was told by a coworker who has a GX460 that it’s imperative to replace/flush the transmission fluid completely every 30,000 miles. I’m curious if this is what others have found is the best solution.

 

[FloydtheQPilot]

The 's GX (2014 base mdl) started this issue last summer.
This thread showed me how to clear the codes and got us home from the Finger Lakes, so thank you.
She refuses to drive in manual mode, she's doesn't like the feel and is afraid of over revving the engine...But she will wield a 10mm wrench and clear her own codes so she can get home from work.

I am in the middle of the Sonnax Zip kit install. "Just" have to drop in the check balls and reassemble everything.
There is a discrepancy for one check ball location in the Sonnax instructions in the upper valve body. The gasket plate between the valve bodies doesn't lie though and confirms proper placement.

Just want to say that if anyone else is contemplating this, you need to get a tub of Assemblee Goo, the green not the blue. It's the high tack stuff. https://www.napaonline.com/en/p/BK_...rge-scaApyAEALw_wcB&gclsrc=aw.ds&gad_source=1

Learned about it from this video :. absolute life saver, no mention of the this stuff in the FSM.

This video at 19min, shows where one of the keeps lives that falls out and is not obvious where it came from...cost me and hour plus of chaos management.

You will need this to "goo in" 3 keepers that are not under tension from the spool valves and the Spring Ball that will fall out of the transmission when you pull the valve body. There is no way to install this without the Goo unless the transmission is out of the rig and upside down on a bench. There are also three grommet seals that need to be gooed in place to the trans before valve body reinstallation and three 4 accumulator pistons. 3 of the 4 have o-rings and should stay in place, but I'm not going to trust that. and the 4th is a slip fit and if not gooed in, will not stay. Gravity is working against the assembly.

This is not a job for the faint of heart. I'm a degreed ME and design and manufacture machine-guns for a living...this job has made me question my choices a couple times.


I'll let you know (or rather my wife will let me know) if this gets rid of the codes.

Hands are warmed back up enough, back to the garage....

Thanks for sharing your adventure. I’m a degreed ME and I design gas oil and gas pipelines & facilities. Working on our vehicles always me rethink the decision, but then I realize it’s fun saving the $$ and I know my work.

Hope it works out for you …. Please share if it works…

 

[Rusty Marlin]

I was told by a coworker who has a GX460 that it’s imperative to replace/flush the transmission fluid completely every 30,000 miles. I’m curious if this is what others have found is the best solution.

According to Toyota, WS should be 60K miles. Dextron III & IV every 30K.

 

[Cold Iron]

I'd be leery of the TX/FL deep south connection. TX and FL are two of the to four most populous states, and have known high concentrations of GX's. They're likely to have higher amounts of everything GX-related, but not necessarily higher RATES of failures...

Lexus doesn't report sales of vehicle models by State. But they do have number of dealers per State and it is based on population.

Florida and Texas together don't equal the number of dealers in Ca. And then there are all the other States.

In this thread there are 18 different vehicles listed with locations as follows.
Texas x5
Florida x4
Arizona x2
California x2 (one is an A760E instead of A760F in an IS 350, same symptoms and codes)
South Carolina
Louisiana
Alabama
Tennessee
Mississippi

Sure looks like a deep South connection to me. I see the temps in AZ. and Fl, and here, everyday on the home intranet page at work. Right now

Heat. The difference is heat. January is the coldest month of the year and during the summer the difference increases by a lot.

There is another thread on here from someone in Tucson that I didn't include above. P0894 and p2714 codes of death on an 80k transmission? You start to add weight with bumpers, armor, and throwing things on roof, or towing, you are going to make it worse especially where ambient temperature is high. And that would apply to those in the North as well although don't see anyone listed in this thread or FB they are all in someplace where this month will not be gaining an extra hour of daylight.

Not sure if there really is a fix for this issue once it starts, most likely it is too late. Been down this path with a Dodge truck a long time ago when I did the try American thing. In the end a rebuild or replacement reman is the correct long term answer. But the right answer is to prevent it from happening to begin with.

1) Install an ATF cooler
2) Keep the ATF clean

I was told by a coworker who has a GX460 that it’s imperative to replace/flush the transmission fluid completely every 30,000 miles. I’m curious if this is what others have found is the best solution.

According to Toyota, WS should be 60K miles. Dextron III & IV every 30K.

Lot of debate on the flush and full ATF replacement vs. partial drain and fill. TCCN says 60K IIRC and only do a drain and fill and skip the filter replacement on the first one. I don't disagree with that but would not be against the 30K drain and fill either.

ATF has a lot of detergents and cleaning agents in it and doing a full replacement I believe is what can cause issues for some. Why there are those that says to not do a full flush especially on higher mileage trannies. It lets loose a bunch of debris and not sure that I buy into the friction material holding things together train of thought. I shoot a lot of shotgun clay targets and my cleaner of choice is homemade Ed's Red gun cleaner developed by the US military at the Frankford Arsenal, Cleaner No.18. Original version contained sperm whale oil but sperm whale oil is kind of scarce as of late so it has been replaced with ATF. 50% of the mixture is ATF. Throw my choke tubes in a glass jar of it and the next morning they are bright and shinny. ATF has a LOT of cleaning agents in it.

I really like TCCN been watching him for a number of years. Yesterday he released a new video of his history of leaving a Toyota dealer to go out on his own, to me it was fascinating and well worth the watch. It is the American dream come to life.



In it he mentions the Japanese improvement process of Kaizen several times. For a mechanic that has worked for someone else to understand Kaizen is amazing in my mind. When Dr. Deming left England and came to the US to try and convince American companies of his quality controls methods the US companies wanted nothing to do with it. So he ended up going to Japan. In the 60's I recall well if something broke a common saying was "it must be made in Japan", because it was junk. The Japanese listened to him and adapted his principals and here we are now buying Japanese made vehicles. In large part for most of us for reliability especially compared to American made vehicles.

The tenants of Kaizen are part of the Deming process. Those that actually do the work know as well or better than those above them in the management or engineering process. Everyone should have an equal share of the design and manufacturing processes, and maintenance. I'll take the advice of an experienced Toyota master mechanic like TCCN over what Toyota recommends from the factory all day long and every day. Especially seeing how Toyota is trying to reduce total cost of ownership numbers for marketing as well as meet US CAFE standards. Lifetime fluid my arse.

 

[Rusty Marlin]

Well . just got the 4lo-check engine-limp-mode-failure.

The Sonnax S147741ZK valve body kit didn't fix it.

 

[r2m]

Lexus doesn't report sales of vehicle models by State. But they do have number of dealers per State and it is based on population.

View attachment 3808684

Florida and Texas together don't equal the number of dealers in Ca. And then there are all the other States.

In this thread there are 18 different vehicles listed with locations as follows.
Texas x5
Florida x4
Arizona x2
California x2 (one is an A760E instead of A760F in an IS 350, same symptoms and codes)
South Carolina
Louisiana
Alabama
Tennessee
Mississippi

Sure looks like a deep South connection to me. I see the temps in AZ. and Fl, and here, everyday on the home intranet page at work. Right now

View attachment 3808685

Heat. The difference is heat. January is the coldest month of the year and during the summer the difference increases by a lot.

There is another thread on here from someone in Tucson that I didn't include above. P0894 and p2714 codes of death on an 80k transmission? You start to add weight with bumpers, armor, and throwing things on roof, or towing, you are going to make it worse especially where ambient temperature is high. And that would apply to those in the North as well although don't see anyone listed in this thread or FB they are all in someplace where this month will not be gaining an extra hour of daylight.

Not sure if there really is a fix for this issue once it starts, most likely it is too late. Been down this path with a Dodge truck a long time ago when I did the try American thing. In the end a rebuild or replacement reman is the correct long term answer. But the right answer is to prevent it from happening to begin with.

1) Install an ATF cooler
2) Keep the ATF clean





Lot of debate on the flush and full ATF replacement vs. partial drain and fill. TCCN says 60K IIRC and only do a drain and fill and skip the filter replacement on the first one. I don't disagree with that but would not be against the 30K drain and fill either.

ATF has a lot of detergents and cleaning agents in it and doing a full replacement I believe is what can cause issues for some. Why there are those that says to not do a full flush especially on higher mileage trannies. It lets loose a bunch of debris and not sure that I buy into the friction material holding things together train of thought. I shoot a lot of shotgun clay targets and my cleaner of choice is homemade Ed's Red gun cleaner developed by the US military at the Frankford Arsenal, Cleaner No.18. Original version contained sperm whale oil but sperm whale oil is kind of scarce as of late so it has been replaced with ATF. 50% of the mixture is ATF. Throw my choke tubes in a glass jar of it and the next morning they are bright and shinny. ATF has a LOT of cleaning agents in it.

I really like TCCN been watching him for a number of years. Yesterday he released a new video of his history of leaving a Toyota dealer to go out on his own, to me it was fascinating and well worth the watch. It is the American dream come to life.



In it he mentions the Japanese improvement process of Kaizen several times. For a mechanic that has worked for someone else to understand Kaizen is amazing in my mind. When Dr. Deming left England and came to the US to try and convince American companies of his quality controls methods the US companies wanted nothing to do with it. So he ended up going to Japan. In the 60's I recall well if something broke a common saying was "it must be made in Japan", because it was junk. The Japanese listened to him and adapted his principals and here we are now buying Japanese made vehicles. In large part for most of us for reliability especially compared to American made vehicles.

The tenants of Kaizen are part of the Deming process. Those that actually do the work know as well or better than those above them in the management or engineering process. Everyone should have an equal share of the design and manufacturing processes, and maintenance. I'll take the advice of an experienced Toyota master mechanic like TCCN over what Toyota recommends from the factory all day long and every day. Especially seeing how Toyota is trying to reduce total cost of ownership numbers for marketing as well as meet US CAFE standards. Lifetime fluid my arse.

Regarding heat in certain states, here in San Clemente, people used have license plate frames with, "Best Climate".
For a long time, didn't really understand that, because we'd have a bunch of overcast/cloudy days. Then I realized that it referred to the difference from daily high temp to the daily low temp, which is quite often only 5° F - 10° F over a 24 hour period, almost year round.
But... That doesn't take into account wheel'n out in Death Valley or some of the other more extreme locations we go!

 

[FloydtheQPilot]

Well . just got the 4lo-check engine-limp-mode-failure.

The Sonnax S147741ZK valve body kit didn't fix it.

Bummer, Rusty. Sorry to hear.

Changing C & D solenoids: no help
Changing all solenoids: no help
Changing valve body: no help

I’m wondering if fluid is passing a seal or a back-pressure valve or something else?

Anybody got any ideas?

 

[BlkGX2011]

Haven't kept up with the thread in a bit but I was thinking that the only way to resolve the issue is to rebuild the tranny. They make this rebuild kit that I was interested in (there's even a manual for it): Toyota A760E A761E Rebuild Kit A760 A761 Transmission Master Banner Overhaul Set A760F A760H Lexus - https://www.oregonperformancetransmission.com/product/OPT-A760-RB.html

It has pretty much everything needed. Not sure what the cost is to have a shop rebuild the transmission but if you add the labor plus materials, I figure it'll beat the price of a re-manufactured one (although you do have to deal with more down time and maybe more research into shops etc).

I think the issue is going to be with the clutches. The 2 speed sensor probably detect too much slippage given the trans oil temp. The clutches probably wear out more for southern cars due to heat and extended oil change intervals (ie. >60k-mile oil change intervals).

If I had the time & money, I would give this a try now but it may be a while before I can be a guinea pig.

 

[bladewerk]

I had a shop install a new OEM valve body with WS fluid and it only made it worse! Just decided to go ahead and get the reman installed now

 

[thescreensavers]

According to Toyota, WS should be 60K miles. Dextron III & IV every 30K.

Why wait? There is no requirement to wait , 30k is a great interval of you want to maintain your trans do your maintenance. CCN is a great mechanic but he isn't sensitive to the specific issues with the GXs trans, he is talking generally.

The solenoid codes we are talking about in this very thread are highly related to how dirty the trans fluid is. Constant shifting and solenoid activation with dirty fluid wears out the bores (as documented by Sonnax)

1) Install an ATF cooler
2) Keep the ATF clean


Lot of debate on the flush and full ATF replacement vs. partial drain and fill. TCCN says 60K IIRC and only do a drain and fill and skip the filter replacement on the first one. I don't disagree with that but would not be against the 30K drain and fill either.

ATF has a lot of detergents and cleaning agents in it and doing a full replacement I believe is what can cause issues for some. Why there are those that says to not do a full flush especially on higher mileage trannies. It lets loose a bunch of debris and not sure that I buy into the friction material holding things together train of thought.

These transmissions "generally" regardless of climate should run similar operating temperatures since they have two coolant cooling/heating loops. Towing , hills ...etc can obviously change this but I don't necessarily buy that Southern GXs have more issues but, like you mentioned statistically there are more GXs here.

Your 1 and 2 points are exactly correct which is why a transmission cooler and filter and frequent fluid changes should be done to protect the transmission and valve body to extend their life

My 48k transmission fluid was jet black and bunch of debris, can only imagine double that miles what can accumulate without being filtered. The valve body has tiny passage ways so these can easily get clogged up if that debris makes its way into the pickup.

Let's not forget transmission fluid has to have the correct balance of "friction" in order to function smoothly. Too much friction you get harsh shifts to too little you'll have bunch of slipping. so yea there is no way a transmission would function correctly if the clutch material was loaded into the fluid. This is another reason why people report their trans shifts so much better with a fresh additives added to their depleted fluid.

 

[Cold Iron]

Why wait? There is no requirement to wait , 30k is a great interval of you want to maintain your trans do your maintenance. CCN is a great mechanic but he isn't sensitive to the specific issues with the GXs trans, he is talking generally.

The solenoid codes we are talking about in this very thread are highly related to how dirty the trans fluid is. Constant shifting and solenoid activation with dirty fluid wears out the bores (as documented by Sonnax)




These transmissions "generally" regardless of climate should run similar operating temperatures since they have two coolant cooling/heating loops. Towing , hills ...etc can obviously change this but I don't necessarily buy that Southern GXs have more issues but, like you mentioned statistically there are more GXs here.

Your 1 and 2 points are exactly correct which is why a transmission cooler and filter and frequent fluid changes should be done to protect the transmission and valve body to extend their life

My 48k transmission fluid was jet black and bunch of debris, can only imagine double that miles what can accumulate without being filtered. The valve body has tiny passage ways so these can easily get clogged up if that debris makes its way into the pickup.

Let's not forget transmission fluid has to have the correct balance of "friction" in order to function smoothly. Too much friction you get harsh shifts to too little you'll have bunch of slipping. so yea there is no way a transmission would function correctly if the clutch material was loaded into the fluid. This is another reason why people report their trans shifts so much better with a fresh additives added to their depleted fluid.

20 years as a propulsion engineer in the Navy doing Engineering Casualty Control. Last 28 years Level 3 Technical Support for Computer Systems, I'm the guy that they keep in the basement and call when no one else can figure out what the problem is. So can't help myself, the heat issue and geo location jumps out at me and smacks me LOL.

Between the Deep South and here the temperature difference is more extreme than I think most people realize. This morning temps

But an hour South of the cabin I stay at during the month of October right now it is

Quite a difference compared to Fl. and Tx. right now although they are colder than normal. During the summer it is the same. In the 70's I took a Greyhound from San Diego to Upstate NY when I was being transferred and at the bus station in Texas the TV said more than 100 people had died from the heat wave. Shocked me at the time. Of course AC wasn't that common back then but people weren't dying of heat up North.

The temperature difference is large enough that the trannies in the South struggle. Of course they can in the North as well if you tow or carry enough weight. Couple of months ago ran across a post on the Tundra forums titled A760F issues, perfect example of heat killing the tranny. In the South. Guy is from WV but was in Texas when the heat destroyed his

=============================================

Last summer I had driven my Tundra (170k miles) down to Texas from WV. During said time I was running the truck back and forth from San Antonio to Austin where the temps on the dash were reading 110F to 114F outside. Well on one of the trips I had a transmission overheating warning pop up on the dash and started getting slipping in 6th. Pulled over and let it cool for a while, when I resumed my trip I locked it into S4 and took it easy. Took the truck to a dealership out there, they said they couldn't replicate the issue.

When I got back home to WV, I took the truck into the dealership, asked for a drain and fill to get rid of the cooked fluid.

About a month down the line I lost 5th and 6th completely (P2714 DTC). When looking through the service history to see if the previous owner ever had serviced the fluid I stumbled upon my last service and read further into what they performed... A BG Fluid exchange, which to my knowledge is a flush... Now Toyota is saying I need a new transmission.

I've swapped both input and output revolution sensors on the transmission, performed my own fluid level check (within spec).

My questions are:
Could that flush have clogged the valve body, thus just needing cleaning?
Could that flush have caused said clog making Toyota responsible?
Is Toyota just throwing the parts cannon at it recommending an entire new transmission based on one DTC?

I'm at a loss here... One is either labor cost at a transmission shop, the other is about $6500....

=============================================

IMO and just guessing here, but the heat is destroying (removing and letting loose) the friction material on the clutch friction plates and transmission bands. A number of people have noticed the friction material in the used oil it is hard to see and requires a strong light behind a sample to see it. Mixed with ATF you essentially have lapping compound. You can replace solenoids, sensors, valve body etc. but the damage is already done to the clutch pack. Why it takes a rebuild or replacement tranny to resolve at least long term.

But that is just speculation on my part and hoping to avoid the issue altogether by keeping it cool and making sure the ATF is clean. Even in the North. I have more concern about replacing the radiator and water pump at or before ~100K personally.

 

[thescreensavers]

20 years as a propulsion engineer in the Navy doing Engineering Casualty Control. Last 28 years Level 3 Technical Support for Computer Systems, I'm the guy that they keep in the basement and call when no one else can figure out what the problem is. So can't help myself, the heat issue and geo location jumps out at me and smacks me LOL.

Between the Deep South and here the temperature difference is more extreme than I think most people realize. This morning temps

View attachment 3819376

But an hour South of the cabin I stay at during the month of October right now it is

View attachment 3819385

Quite a difference compared to Fl. and Tx. right now although they are colder than normal. During the summer it is the same. In the 70's I took a Greyhound from San Diego to Upstate NY when I was being transferred and at the bus station in Texas the TV said more than 100 people had died from the heat wave. Shocked me at the time. Of course AC wasn't that common back then but people weren't dying of heat up North.

The temperature difference is large enough that the trannies in the South struggle. Of course they can in the North as well if you tow or carry enough weight. Couple of months ago ran across a post on the Tundra forums titled A760F issues, perfect example of heat killing the tranny. In the South. Guy is from WV but was in Texas when the heat destroyed his

=============================================

Last summer I had driven my Tundra (170k miles) down to Texas from WV. During said time I was running the truck back and forth from San Antonio to Austin where the temps on the dash were reading 110F to 114F outside. Well on one of the trips I had a transmission overheating warning pop up on the dash and started getting slipping in 6th. Pulled over and let it cool for a while, when I resumed my trip I locked it into S4 and took it easy. Took the truck to a dealership out there, they said they couldn't replicate the issue.

When I got back home to WV, I took the truck into the dealership, asked for a drain and fill to get rid of the cooked fluid.

About a month down the line I lost 5th and 6th completely (P2714 DTC). When looking through the service history to see if the previous owner ever had serviced the fluid I stumbled upon my last service and read further into what they performed... A BG Fluid exchange, which to my knowledge is a flush... Now Toyota is saying I need a new transmission.

I've swapped both input and output revolution sensors on the transmission, performed my own fluid level check (within spec).

My questions are:
Could that flush have clogged the valve body, thus just needing cleaning?
Could that flush have caused said clog making Toyota responsible?
Is Toyota just throwing the parts cannon at it recommending an entire new transmission based on one DTC?

I'm at a loss here... One is either labor cost at a transmission shop, the other is about $6500....

=============================================

IMO and just guessing here, but the heat is destroying (removing and letting loose) the friction material on the clutch friction plates and transmission bands. A number of people have noticed the friction material in the used oil it is hard to see and requires a strong light behind a sample to see it. Mixed with ATF you essentially have lapping compound. You can replace solenoids, sensors, valve body etc. but the damage is already done to the clutch pack. Why it takes a rebuild or replacement tranny to resolve at least long term.

But that is just speculation on my part and hoping to avoid the issue altogether by keeping it cool and making sure the ATF is clean. Even in the North. I have more concern about replacing the radiator and water pump at or before ~100K personally.

There are many factors at play when it comes to failure analysis, one would need to do an Root cause analysis - Wikipedia - https://en.wikipedia.org/wiki/Root_cause_analysis. Your hypothesis can surly be one of many many factors at play. The running gear of the GX460 is largely unchanged from the gx470, if you look up part diagrams they use a lot of the same parts. The main differences are for one the valve bodies.

The Tundra post does not make much sense to me throwing the overheat warning on the dash means the trans hit 300F+ which is not normal, towing in drive without a locked TC can roast the fluid!. Besides the guy/gal had 170k when the dreaded solenoid codes popped up, the overheating of the trans did not help it live any longer the codes would have popped up either way.

Do your fluid maintenance, Keep the transmission cool, and install a filter in the cooler line to keep the valve body from wearing and keep driving on.

 

[Rusty Marlin]

I had a shop install a new OEM valve body with WS fluid and it only made it worse! Just decided to go ahead and get the reman installed now

View attachment 3816456

View attachment 3816457

that doesn't make me feel any better, somehting else to save for cuting into my gun budget.

 

[yeLwWm]

I have the same P2714 problem with 2008 LX 570, AB60F trans. I just applied the TransGo kit, link:

Fixed P2714 on 08 LX 570, probably dealer put the wrong trans oil filter

My 2008 LX 570 (210K miles) showed P2714 (Pressure Control Solenoid D Performance/Stuck Off) last year after dealer serviced the trans, the first time it showed up with stuck at 4th gear not going to 5/6th gear. The trans is AB60E, 6 speed. So I pulled over and restarted the engine then drive...

forum.ih8mud.com

Currently, after the second correct installation, it works fine for a week. I hope it can provide some useful information and clues to everyone.

 

[toy_tek]

I’m shopping for a 460 and ran across this thread - glad I did. Read the entire thread.

Two questions:

Has anyone tested the two temp switches on the trans for correct resistance range and operation?

Wondering if anyone had tried using Lube Guard (black bottle) to see if there’s any positive effect? I’ve used it with excellent results in other Toyota auto applications, after recommendation from a good friend who’s run a transmission shop for 30 years.

 

[Bdog0820]

There are many factors at play when it comes to failure analysis, one would need to do an Root cause analysis - Wikipedia - https://en.wikipedia.org/wiki/Root_cause_analysis. Your hypothesis can surly be one of many many factors at play. The running gear of the GX460 is largely unchanged from the gx470, if you look up part diagrams they use a lot of the same parts. The main differences are for one the valve bodies.

The Tundra post does not make much sense to me throwing the overheat warning on the dash means the trans hit 300F+ which is not normal, towing in drive without a locked TC can roast the fluid!. Besides the guy/gal had 170k when the dreaded solenoid codes popped up, the overheating of the trans did not help it live any longer the codes would have popped up either way.

Do your fluid maintenance, Keep the transmission cool, and install a filter in the cooler line to keep the valve body from wearing and keep driving on.

We need a transmission expert at this point to tear down these transmission and find the true root cause. Keep in mind. I am from Northern California. Very temperate climate. I have an IS 350 RWD with the A760E and I'm facing the exact same issue. This problem start 2.5 years ago/50,000 miles ago. Transmission still shifts completely fine. The code only pops up if I'm in drive and its a cold start (summer time or not and its a 50/50 chance it'll happen.) I can keep it in drive for eternity during that drive cycle and no issues. I'm assuming the reason the code/limp mode doesn't occur in S because the computer tolerance for the command of the shift solenoid and the expected RPM/speed ratio is higher or ignored. Regardless. the fact that I have been getting away with this for so long indicates an electronic issue or not anything mechanical related. People have mentioned replacing the valve body did not fix it. So I'm unsure at this point.

 

[Bdog0820]

I have the same P2714 problem with 2008 LX 570, AB60F trans. I just applied the TransGo kit, link:

Fixed P2714 on 08 LX 570, probably dealer put the wrong trans oil filter

My 2008 LX 570 (210K miles) showed P2714 (Pressure Control Solenoid D Performance/Stuck Off) last year after dealer serviced the trans, the first time it showed up with stuck at 4th gear not going to 5/6th gear. The trans is AB60E, 6 speed. So I pulled over and restarted the engine then drive...

forum.ih8mud.com

Currently, after the second correct installation, it works fine for a week. I hope it can provide some useful information and clues to everyone.

Really appreciate this. Definitely keep us updated. The line pressure boost makes the most sense based on how my transmission feels and reacts. It seems abnormally soft during the first few minutes of driving.

 

[thescreensavers]

We need a transmission expert at this point to tear down these transmission and find the true root cause. Keep in mind. I am from Northern California. Very temperate climate. I have an IS 350 RWD with the A760E and I'm facing the exact same issue. This problem start 2.5 years ago/50,000 miles ago. Transmission still shifts completely fine. The code only pops up if I'm in drive and its a cold start (summer time or not and its a 50/50 chance it'll happen.) I can keep it in drive for eternity during that drive cycle and no issues. I'm assuming the reason the code/limp mode doesn't occur in S because the computer tolerance for the command of the shift solenoid and the expected RPM/speed ratio is higher or ignored. Regardless. the fact that I have been getting away with this for so long indicates an electronic issue or not anything mechanical related. People have mentioned replacing the valve body did not fix it. So I'm unsure at this point.

I believe we already know the issue Read Diagnosing Solenoid Performance Faults in A761, AB60 & A960 6-Speed Transmissions - https://www.sonnax.com/tech_resources/345-diagnosing-solenoid-performance-faults-in-a761-ab60-a960-6-speed-transmissions

Based on the Sonnax documentation we know that valve body wear is the Crux of the issue. What causes valve body wear? Dirty, abrasive fluid.

Do your trans maintenance. At 48k my trans had lots of debris in my drain pan from a easy drain and fill. Id recommend dropping the pan to clean the magnets. I've also installed a Magnefine filter and cooler (see my other posts) to protect my trans.