Here in Charleston sc is a bit tricky sometimes, I have a commercial account with them but I prefer to buy online on their dealer parts website, cheaper and just put pick up. (10 minutes from me)
GX460 P2714 P0761 Ultimate Summary and Hope For A Fix Thread
- Thread starter StriderWolf
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Something I’m finding after each trip through the VB/valves/seals: I always put 1 qt more in than before disassembly bc of what doesn’t make the bucket, spills, drips, tools covered in fluid, etc. I usually drive it for a day before setting the fluid level correct per the level truck method. The truck drives better with extra fluid than with the proper amount. A lot better. Better shifts, less delayed shifting. I believe the reason for this is because of the bonded seals leaking. When they leak and you don’t have enough pressure/fluid to shift/push the clutches together, then it gets delayed until the fluid can be recirculated. Based on the intake of the filter, I think the pan design allows for just enough fluid to make the shifts, no more than needed to move the next piston. When I got this truck it was 1.5 QTs over full. I’ve mentioned this before. I’m returning to an overfilled condition
Anyone consider taking their faulty transmission to a reputable transmission shop to have them diagnose and fix the issue?
I just replace my entire transmission and I would have done it but it wasnt justifiable with the time/money itd take. Maybe someone else does?
The video from justcallmeeddie1 shows that the tundra transmission issue was probably from old o-rings. Maybe if there's a few cases from transmission shops that report the same thing, we'll get closer to an answer.
I just replace my entire transmission and I would have done it but it wasnt justifiable with the time/money itd take. Maybe someone else does?
The video from justcallmeeddie1 shows that the tundra transmission issue was probably from old o-rings. Maybe if there's a few cases from transmission shops that report the same thing, we'll get closer to an answer.
I find it interesting that the A750F does not have the O-ring problem. My O-rings are 19-years old with 202K on them and the trans shifts great. I'm wondering if it's due to just the heat/transmission fluid issue (no aux cooler on the GX460) or a change in the O-rings or some other part.
Well, I know what the problem is. (Everything is worn out and cooked bc of design failure with each failure occuring at a separate point but for the same reason). And I know what a transmission shop would recommend, bc it’s their answer to everything and how they make the most amount of $. Trans shops are not interested in finding an inexpensive mitigation. And they shouldn’t be. Their effort should be in providing a warrantable solution for the most amount of profit possible.
My intent here is to find a way to avoid the inevitable for as long as possible, to fully understand what the failure is, and go through the challenge of repairing it first with the least amount of $ possible. I enjoy understanding the fluid dynamics, wear patterns, failure points. I’m an engineer, if have the “i’tis”
. I hope someone else benefits from my effort. I’ve learned a ton, but I enjoy working on cars too.
Did you already change all oring from the accumulator and the sonnax c1 too?
Did you already changed your orings accumulator and the sonnax c1 too?Well, I know what the problem is. (Everything is worn out and cooked bc of design failure with each failure occuring at a separate point but for the same reason). And I know what a transmission shop would recommend, bc it’s their answer to everything and how they make the most amount of $. Trans shops are not interested in finding an inexpensive mitigation. And they shouldn’t be. Their effort should be in providing a warrantable solution for the most amount of profit possible.
My intent here is to find a way to avoid the inevitable for as long as possible, to fully understand what the failure is, and go through the challenge of repairing it first with the least amount of $ possible. I enjoy understanding the fluid dynamics, wear patterns, failure points. I’m an engineer, if have the “i’tis”
Yes, I changed all my valves and springs (prob a waste of time & $), all the O-rings (I recommend), the C1 with the Sonnax kit (I recommend), the ball check valves spring (I recommend), the flat seals and tube seals , 3&3 (I recommend), the zip kit (iffy).
I guess full report is due: Great forward shift improvement while in the same piston (makes sense. Ask questions if you don’t understand what I’m saying or why). Still have slight hesitation from first piston to second for the first and second shift from cold. After that no problem. Weak reverse available when in an overfilled condition (experimenting here. Currently at 1.5 QTs over. Going to add 1 qt at a time until adverse effects). No more codes thrown. Still have reverse on demand or after 1-3 second delay when over 155 F. To get full reverse in proper fluid level condition when cold, need to rev up to 5K+ to fill piston/outrun leakage.
Considering adding another bottle of Lucas to increase viscosity, especially in cold conditions.
It’s clear to me now that the bonded piston seals are worn/damaged. Heat helps reduce leakage. Increased viscosity and increased fluid availability help outrun/reduce leakage. A rebuild is ultimately necessary to replace pistons and O-rings. This is what a trans shop is going to tell you. And they are right.
Ok ok, hopefully I will receive everything tomorrow, seals, orings and sonnax c1, lets see if not, I will sell the valve body and put a new transmission, I bought this 2011 gx460 in $2000, so I have room to put money, the lady who owned this one told me what the transmission shop told her the problem was 2 solenoids and they wanted to put a new transmission and was 9k total. Thats why she sold it cheap.
If you don’t already have a tub of green goop, get one. You cannot put the VB back in without gooping the ball check valve, Sonnax valve, flat seals, and maybe the three valves in place. And the ball check valve needs to be double checked just before putting the VB in place. It’s the one that wants to fall out first. The new O-rings on the Sonnax valve should hold it in place. Before I replaced the flat seals, I had a flat seal fall out and onto the top of the VB without knowing it. I ended up reinstalling the VB with a flat seal blocking the middle port. Made the second piston shift, especially 5-6, really screwy.
I told a friend to help me installing the vb because of the check ball, one holding the vb and putting the hook and the other checking the seals and holding the checkball, lets see, what green goop can I use in the transmission to hold the seals and the ball?
You can use as much as needed. But it dissolves in transmission fluid really fast. For the check valve, I just fill up the square pocket completely before inserting the spring and check valve.
Ok ok, basically same for the engine. I can do engines but Im a puss1 with transmissions and A/C
Similar to red n tacky. But it’s made just for transmissions. It won’t impact the tranny fluid properties. Ive never used red n tacky for engine assembly, but it’s a close comparison in texture. And i wouldnt use engine assembly grease for the tranny. Maybe somebody here has, maybe it’s fine.Ok ok, basically same for the engine. I can do engines but Im a puss1 with transmissions and A/C
- Thread starter
- #614
This is SUPER helpful as I don’t fully understand it all and haven’t until your explanation as it makes sense why the temp warming allows normal shifting.
I have 2 questions based on your theory….
1) Would truly a rebuild do it or would we think most shops would just recommend a new transmission due to warranty and labor?
2) Regardless of rebuild or new transmission, what then prevents this happening again? It appears as though models post 2010-13 don’t have as many issues reported, was something changed so it’s less of an issue? Yes we all know, change fluid everything 30-50k, but many put on a transmission cooler, does this help? Is it needed?
So let’s say this entire thread tracks don’t the issue as reported and it’s a rebuild or new transmission. Will it happen again with the design of these?
Thanks for all your info and work on this!
Shops are going to sell you the most profitable option that has the least probability of returning and costing them. That’s usually a new/rebuilt by a reputable supplier.
I don’t really know the difference between a Toyota rebuilt and paying to have a shop do it. Both are likely higher quality than I’ll have after I finally rebuild mine. But $, right?
When I finally pull mine, it will go back in with an additional cooler and will be serviced every 30K miles. Not sure if this will help, but I don’t think it can hurt and I plan on towing a boat. As to what the initial failure condition is, it’s in the engineering. The parts and design were not properly spec’d for the common use. Was this corrected at some point? I’d say yes since there are rumors of tech bulletins out there and the failures seem more common in Gen 1. I don’t know failure rates of newer trucks, but the mileage 150-200K seems to be common. 2010 models would be around 192K on average at 12K/year. Do the failures in later years increase as mileage gains? If so, the 2014’s should be approaching failure now. I wouldn’t guess how you’d track this. Overall, I would not expect more than 180K miles out of a rebuilt. By that time, I’ll be approaching 360K in mine, likely the lifespan of most of the trucks components.
I forgot to mention the Lucas additive in my previous post. I wanted to add another bottle as part of my overfilled condition experiment. But I watched a video about the leak repairing properties. Turns out, you should not expect immediate results, and it may take months for the product to soften the seals/O-rings enough. So I’m going to hold off. Additionally, Toyota calls for a LV spec fluid. And the Lucas increases viscosity, so I’m not sure what other adverse impacts it could have by pushing it too far. So I’ll wait on that for now. I’m going to add another Qt of fluid this weekend. Still questionable reverse on short trips. Still weak reverse power when cold, no reverse power without high revs prior a longer drive
- Thread starter
- #616
Awesome! Thank you!
Acrad
GOLD Star
There was a TSB for an ECM update for 2010 models
I thought there was one on fluid. Definitely could be wrong. Couple things here. My truck was sold by the same dealership 2X. The second as a certified truck. Possibly a third time at the auction. My truck was 1 1/2 QTs over filled when I got it. The Lexus service history has some real questionable notes about servicing the air pump when the owner complained about shifting issues. My truck doesn’t have an air pump. This was addressed multiply times while under warranty. There’s mention above of somebody taking their truck to a trans shop and had them tell him it was 1 1/2 QTs low after he checked fluid using FSM method.
- Thread starter
- #619
Thanks Acrad! Would this WCM update likely help “a bit” with some issues? I know when I reached out to my local Lexus dealer they did mention that after a new transmission install, they would be updating some of the computer components as well.
- Thread starter
- #620
Funny enough, my GX460 was getting less closed when I did my own fluid exchange as I overfilled it a bit. I took it later to have them properly adjust the fluid level and it had more codes after that point.
I say more codes as my current shifting issues are not as bad as others on this thread yet. Sport shifting solves 100% of our issues still at this point after 2 to 3 years. But with the overfill, we were getting less codes when we just didn’t sport shift, even when it was cooler temperatures in Colorado. I was just curious to test it after a full exchange.