Poll: Transmission Software TSB (longer term) Feedback

It might just be shifting between fourth and fifth depending on the speed, recommend getting the TSB first to see if it holds the gear longer. Sometimes I can only tell it shifts when I see the rpms change. Grade of the slope and speed might catch you between gears at times too causing it to shift back and forth.

TSB will reduce the shifting frequency but not completely eliminate it

 

I agree with JS.

 

The 3 to 4 flair is the common denominator between the A750E 5 speed and the AC60E 6 speed series transmissions .
The A750E transmission that was built for the 2nd gen transmission has a flair on the 3-4 upshift when cold .
There were many complaints and no fix from Toyota .
I believe the aftermarket has a fix for the flair but it has " NOT " been released for the 6 speed but is available for the 5 speed . A very common problem .
Leaking end plugs on the valve body are a possible and probable cause . The end plugs are cool and havnt expanded allowing hydraulic pressure to drain to the transmission pan . This issue occurs on brand new transmissions .
Here is the fix for the 5 speed http://www.sonnax.com/parts/1783-o-ringed-end-plug-kit
The fix above compensates for a leaky hydraulic circuit but not because its worn out as stipulated in the Sonnax guidelines . The circuit leaks because the transmission is cold and is not up to proper temp which should be 180 degrees .
Its very difficult trying to look at a pressure deficiency when connected to the Techstream scanner and most Toyota techs would most likely give up diagnosing a cold flair if the scanner didn't have any feed back for them .
This is where the aftermarket takes the time to figure out where the bugs are and come out with affordable fixes .

For the guys with a 3 to 4 flair , try allowing your truck to warm up to operating temp and then take your truck for a drive feeling for the flair and I will bet it will be gone or very minimal .
I noticed this issue when my truck was new ( 2010) .
Is it doing damage to your transmission ? of course.... the flair is a slipping clutch
In an ideal world , Aisn Seiki should incorporate these fixes as they update their transmission hardware .
Here is what the aftermarket found to be issues with the 5 speed automatic in the 2nd gen .
http://www.sonnax.com/parts/3477-zip-kit
Because the same company makes the 6 speed , you can expect to see the same issues over time .
Eventually , they will release a kit that fixes the known problems with the AC60 series transmission . I gather that most of the valve body improvements from the 5 speed would fit just fine in your 6 speed transmissions

 

Thank you gearcruncher. You input is very valuable for sure, as I have been told you are an authority with the Aisin transmissions. What you are describing is consistent with my symptoms: as far as the waiting for the truck to warm up and the flair on the 3-4 shift minimizes. I am shocked that Aisin, as reputable as they are, has not fixed this issue in the AC60x. I am tempted to have Toyota take this truck back and replace it with a manual; refunding the difference in invoice cost. I really don't want to be a guiney pig, unless they are appropriatly compensating me for the aggregation.

 

My response with 2500 miles since update is yes, yes, and yes.
However, it seems like tranny has now started to miss gears again (hits rev lim. and takes a sec to engage when doing kick down), which it has not done since before I had fluid added at 5000 miles. Now at 12500 miles. Other than the tranny I freaking love the truck, and all the other fixes have held true.

 

I agree that the cold upshift flair to 4th gear should be addressed in your new truck , but I doubt enough owners have complained about the problem for Toyota to jump in and rectify the problem .
It took almost a year and pretty much every member at Tacoma world phoning corporate and complaining that their fluid was low and the transmission delayed from reverse to drive on their new truck before Toyota released a TSB .
With this said , I knew there was a serious issue with my new transmission when cold . Just before the transmission upshifts to 4th when cold , I let off the gas pedal to allow the transmission to smoothly upshift into 4th which prevents the flair

 

Yes, I also release the throttle, when shifting to 4th, to try and preserve the clutches. I have about 450 miles on the truck. I have the truck at the dealership, for the 3rd time now so they can capture the problem on the Techstream. I have already given the service manager 6 videos of the transmission flairing 3-4 (about 1000 RPM flair). Hopefully Toyota will PROPERLY fix my transmission, or I simply do not want the truck anymore.

 

Sounds like you may have a severe case and enough proof to back up your complaint .
Considering Toyota dealers dont touch valve bodies , the most probable outcome is a new transmission .
The unfortunate rectification to this is the fact that your concern is a common problem and can be repaired quickly but Toyota chooses to simply swap out your new transmission for another new transmission with the same issue and the same internal parts .
Let us know how you make out . Keeping my fingers crossed that they come out with a fix .
You could always show the dealer techs how the aftermarket fixes this

 

I am following your case closely because this is very frustrating to me too although I'm not observing the transmission flare as consistently as you describe it

 

I will certainly keep the group informed, and I will share the information about the aftermarket fixes. Thank you very much Gearcruncher. If you know of any links to technical manuals on the AC60f, please pm me. Thanks again good sir!

 

I will keep them group informed as things progress smittty.

 

I live in the great white North where the temps are 40 below zero for 6 months .
The 5 speed auto in the 2nd gen has a nasty 3 to 4 flair when cold .
I have driven many 2nd gen Tacoma,s and they all have it regardless of age .
I can only assume the 2016 6 speed has similar issues .

 

It's nearly eighty-five to ninety degrees Fahrenheit here in the mornings in Phoenix Arizona the fact I'm still getting a flare really makes me wonder how bad it will get when the cold weather hits

 

First up: I believe the problems folks are having are real. I appreciate folks sharing their experiences.

This thread is an interesting study in information distortion through the "forum lens". We've got pages of posts about how terrible the transmission is in these trucks, yet the survey is 41 improved to 4 no improvement or worse. There's a lot of "in between" that could be argued either way. That said, improved doesn't mean "completely right". I marked "Improved with a few issues remaining", but overall I am satisfied. After reading this thread I was wondering if I was missing something. Anyway, here's my update:

I've got about 3k miles on the TSB, mostly during two long trips.
- Cruise control - Woo Hoo! I think it works great. I've started using it specifically when going up hills because I like the gear selection and it seems they put some effort into preventing hunting.
- Power when I need it... Before the TSB, it felt like the power was there somewhere, but it could never find it. Now, it gets going NOW. Not a torquey V8, but it gets up and goes when asked (instead of forced).
- Smoother power: I end up on a lot of curvy roads. Abrupt changes in power are a nightmare when cornering, the trans has my back now and I don't have to switch to ECT Power for every set of curves.
- The throttle is so much more linear now (probably not an actual change, but a perception change due to the better gear choices). So much easier to drive in traffic.
- Gas mileage appears to be improved. I chock this up to working cruise control and the fact it is easier to drive smoothly. I could see folks who do a lot of in-town driving getting worse mileage since the power is so much easier to tap.

But:
- I do get flair on the first 3-4 (maybe 2-3) shift on a cold morning. Doesn't really bother me.
- The gear selections are not perfect and they probably could be implemented better in an automatic. It's an automatic, I'm never going to find one that knows exactly what I want, but this one is pretty good now.



Overall, I'm so much happier with the truck now. I just got back from a ~2k mile trip and I loved it. I could vanquish slowpokes going up hills, hang with fast traffic in the curves, and then go driving in the sand.

 

Thank you HalfWay. When I dropped the truck off with the dealer the first time, they gave me a newish Sienna. Now, that vehicle's transmission worked right! Toyota, or Aisin, really screwed up the AC60F. I have never witnessed such a terrible transmission, with the exception of a dying, old transmission. I will be contacting Toyota today looking for a true fix to my dissatisfaction. I do not think they will be able to satisfy my with the AC60F at this time. I think a manual transmission is the current fix for the AC60F.

 

This is why I asked about the Zip Kits in your transmission thread.

 

Gearcruncher, I am curious, did Changing out some of the valve body components, with the Sonnax parts, always fix the 3-4 flair in the 2nd gen Tacomas, in 40 below zero temps? If so was it the end plugs with the o rings? Thanks

 

What is the flair everyone is referring to. I don't understand it. Describe it to me in simply language.

 

The end plugs make a huge improvement but If I was pulling the valve body down , it would be easier to simply install a full Sonnax zip kit and kick all the problems in the @ss .
For you guys with the 2016 , they dont make a full zip kit for your transmission yet and I havnt had an AC60 series transmission apart to determine if any of the aftermarket parts from the A750E 5 speed transmission will fit . I believe the end plugs with the o-rings are similar on your 6 speed . The parts you get for the 5 speed end plugs should fit in the 6 speed .
For the present time , I would personally wait until they release a kit for your transmission . This way when you purchase the kit , it covers all known bugs inside your trans .
Any of you guys good with valve bodies ? or good with a lathe ? it wouldnt take much to cut a groove into your end plugs and install an O-ring to prevent a known problem or you could hold out and let Toyota try and fix it .
You guys are all on warranty

 

Thank you gearcruncher