Weird delayed engagement incident today

Created a case with Toyota, the representative was very helpful and did not feed me any BS like "I've never heard of this". After reviewing the links you guys were kid enough to send me, I gave them the following list of behaviors that didn't seem normal and may be transmission related. The first two are intermittent, the last three are more frequent.

- Slipped into neutral at a stop light, slammed into first gear after 1500 rpm
- Cold start, from P to D the truck is fine @5mph as i loop though the circle i live on, coast a bit then when i straighten out and accelerate the truck feels like it is in neutral then slips back into first
- Thumps into first gear at moderate to hard stop
- Vibration while accelerating 1/2 throttle and gets worse when more throttle is applied through first gear, remaining gears are fine (think highway on ramp)
- A lot of shifting between 4- 5 -6 gears

 

I'd say @gearcruncher is dead on the mark, as usual..!! You got low tranny fluid....AND "possibly" some problems with it being low and going thru this for how long...?? See if you can watch them do the check and see how much they add....!!

Get her checked for sure.

 

Agreed, 5,500 miles so far since I got it this past September. It has only slammed into first gear once, but I think the second issue is related to the first. Hoping that jumping on this prevents any long-term damage. I will give the same list to the dealership. Appointment set for Friday and taking off work to get it in as soon as possible.

 

Good luck man...hope they do good by you..... You WILL notice a great improvement IF they fill it properly..
Guaranteed.... (I did).

 

Might be a stupid question, but would these issues impact MPGs? I used to get 19 average, now down to 15.5-16. Granted its been frigid the past couple weeks (around 10 degrees when I drive around), but the hunting in the 4-5-6 gears has me thinking. Wondering if you saw an increase since yours was fixed

 

Yes, I did, but not by too much.... the "holding" 4th gear after topping the hill (in cruise) was fixed by fillin' her up and any time yer in a lower gear...you are gooder on mileage..!!

 

I know the 4 liter engine runs extremely rich when its cold out . I use all kinds of fuel in negative temps .
Not sure about the 3.5 during the cold stuff

I am fairly certain the dealer will be clearing your adaptive memory after a fluid top off . This will also change how your truck shifts but I do not beleive topping off the fluid will take care of all your concerns .
Consider yourself lucky if it does
The thumping may be related to axle wrap

 

Thanks, I will remember that. My end goal here is to get it to where the transmission doesn't slip into neutral and not slam into first. I just dont want a damaged transmission and I can deal with the truck's idiosyncrasies. The shifting can get a little busy for my taste, but I already know switching it to ECT does the trick for me if i feel like I need it. Axle wrap is ok too, seems like its a pickup thing and I think the tow items below may be due to that and not the transmission, but I want them to be thorough

- Thumps into first gear at moderate to hard stop
- Vibration while accelerating 1/2 throttle and gets worse when more throttle is applied through first gear, remaining gears are fine (think highway on ramp)

 

Have you checked the torque on your rear "U" bolts that hold the springs on..?? Mine were loose from the factory. I can't remember the right torque off hand, but it's worth checking..
There are threads here on that..!

 

Spend some time researching before you take it in .
There are at minimun , a thousand posts at Tacoma World regarding axle wrap and probably just as many posts with a vibration concern on the 2017 trucks

 

S3 or lower. Whether or not this holds true for half lock, I do not know.

If one were to monitor SL and SLU(half-lock-2,3,4,5,6) shift solenoids thru any given transmission scenario(D, D+ECT, S3, S4, S5, S6, S3+ECT, S4+ECT, S5+ECT, S6+ECT) and correlate it to symptoms...might get somewhere.

I have a feeling a lot of the crap in the transmission has to do with the torque converter and lock-up(full or half).
This company has a lock up kit now for overseas 2.8L/AC60F vehicles . Notice the things it fixes...sound familiar?

 

Use to install lock up kits similar to this on GM products but that was before the flex lock up came out .
The guy didnt say anything about check engine lights popping up . Wondering if the kit prevents this from happening

 

There's another video I didn't post that shows a re-program of the ecu.

 

It's a transmission flare. When coming to a stop but not a complete stop the truck is in second gear or limbo (in between gears) when you go to step on the gas there is nothing except rev until the transmission downshift to 1st. The tsb and rear diff recall on my truck was performed and it still does it a little bit especially down hill. You can repilcate with a California rolling stop almost every time unless you are super light on pushing the throttle. Push it like a normal car/truck and it will rev (flare up) then kick as it hits the gear

 

Some members are taking their trucks to the dealership to have the fluid level topped off properly and are still experiencing a delay from reverse to drive . Toyota uses " SQUAWK " control to prevent that initial lurching feeling when the transmission shifts into forward or first gear .
Squawk control selects 2nd gear rather than first gear to remove that lurching feeling . Squawk control is computer controlled and the logic can easily be re-written to improve this.
This is from the low fluid poll back in Dec of 2016 .
The first procedure of squawk diagnosis is checking for proper fluid level .

 

I've heard you mention this before, but could find no reference for it[SQUAWK] specifically.

What I did find were multiple patents for braking/grade logic braking/shift control; which would correlate somewhat to what some owners have observed. It happens in D(AI shift) and downhill grades, and not in S-mode or with ECT mode engaged.

Here's the original link I found them on.http://www.freepatentsonline.com/9676388.html

If you scroll down, you'll find links to other similar patents; some Toyota/Denso, some not. Those links will have additional links; again, some Toyota some not. I suspect this rabbit hole is deep and wide.

Here are just some of the ones in PDF format. Some issued last year; some going back 10+ years. Some issued to Toyota; some to Denso.
http://www.freepatentsonline.com/9676388.pdf

http://www.freepatentsonline.com/7853385.pdf

http://www.freepatentsonline.com/20040014565.pdf

http://www.freepatentsonline.com/20060135315.pdf

http://www.freepatentsonline.com/20060040791.pdf

Addendum-If Toyota is doing copy pasta engineering, it would explain the conflict and shit ton of artifacts found in the ECU. @OVTune truly has his work cut out for him. God bless him.

 

Good to know thanks, I can deal with that. The big concern for me is it slipped into neutral after being at a dead stop for a minute then slammed into gear. Also had a gear slip this morning from either 2nd to 3rd or 3rd to 4th under normal/light acceleration. Nothing big, but was a noticeable thump but ironically it was after 5 minutes of driving like the dead stop incident

 

"....the way Toyota should have..." sounds eerily familiar. Interested to see where this rabbit hole leads though!

 

Small update. Corporate case manager called, very friendly/helpful and was proactive in indicating that they have already contacted the dealer and my service rep has suggested getting the regional whomever in the loop. I was adamant about making sure they knew I was not playing both ends against the middle, just making sure this gets handled properly especially since I am taking vacation time for it. Should receive a call from the service rep prior to my appointment Friday and I will tell her the same thing. I appreciate the shared knowledge and patience with a new taco guy here, I will keep you all up to date

 

Service manager called, she was just as helpful as corporate. Asked to reschedule my appointment for Monday so that the regional service manager (or something like that) can be a part of the process. She said they were definitely going to check the transmission fluid levels manually and will also check other potential causes. She acknowledged that low fluid level has been seen before from factory, but would need to give me a loaner car since they have to let the fluid cool down for several hours to do it properly.