3rd gen torque converter shudder

Are you convinced this is a torque converter shudder or is it a shudder due to the engine locked directly to the transmission and drivetrain ?
There was mention that you were also feeling driveshaft vibrations .
Has either of the dealership service advisors tried to assist you with the driveshaft vibes ?

If the driveshaft vibrates at any speed , you will really feel the vibrations once the converter locks up .
Have you tried matching your shuddering rpm to a stall test yet ?
Has either dealership tried a stall test ? A stall test eliminates the drivetrain .
Seen you private messaged me but I am only going to ask you to try eliminating these possibilities first

I have a document built for diagnosing drive line vibrations and shuddering .
https://www.tacomaworld.com/threads/vibration-diagnostics-for-all-tacomas-write-up.520607/
Process of elimination is the only way you can narrow this down .

 

Obd fusion, use All Cylinder Misfires to see if anything is going on. Use Mode $6 monitor to review misfires per cylinder.
And if you have the issue at 2000 RPMS under a normal load, you need an inspection of the driveline and all other relevant components. This is outside of typical issue we are familiar with.

 

I’m convinced its tc shudder becasue im monitoring tc lock up and vibrations happen when tc is locked.
Dealership service reps dont do anything besides go on test drives with me and tell me this is a normal characteristic of the truck and that they can’t reengineer it no matter how many times i insist my truck has an issue...

ive done the stall test twice and shudder does not occur.

I’m starting to notice that on ect mode, i hardly experience any vibrations besides 40-50mph. I’m actually starting to think I don’t have driveline vibrations at all and that this shudder is the culprit of it all.

at 40-50mph the shudder is there but not as prevelant or high frequency. When im up to around 65mph and around 2000 rpm the shudder feels a lot more like a drive lime vibe and can be felt under my seat buy goes away as soon as truck downshifts or the brake tap test is done ..

 

I finally ran my 87 gas out and just went to fill up with 93 Shell vpower gas. Will clean the MAF sensor and disconnect battery when I get home. Hopefully tommorow morning’s commute is more pleasant.

 

It’s a 2020, do you still think you need to clean the Maf sensor ? Hopefully the 93 gas octane will fix your issue. I have the 2017 and been on 91 octane here in SoCal Since new and never had your issue. Once tried 87 and it drives / feels different. Not as smooth especially going up the mountains so I went back to 91 and never looked back . I also recently had it vf tuned to 2.0 premium a month or so ago and it drives awesome. Did the premium tune because It’s what was recommended by the tuner and I’ve been using premium .

 

It was recommended to me so it’s worth a try... im desperate at this point and dealerships are no help at all

 

Hopefully you’ll get this sorted out. I’m very ocd with vibes or noises On my vehicles . Traded my 2011 taco To a FJ due to driveline vibes after a lift which never got resolved.so now I still haven’t lifted my 2017 taco for fear of having those unwanted vibes haha.

 

Thanks. I’m not much of a materialistic person and vibes dont worry me much but the fact that I got out of a nightmare that included a lawsuit and reliving the damn nightmare again, I’m pretty torn. Im driving my dream truck and i just know it’s not driving as it should. The damn thing isn’t cheap either

 

i just read your diagnosing vibrations thread and read up on the flex lock .. I just took the truck for a drive and did as it instructed. I put the truck i. S4 and there was no shudder even though TC was locked. I was also monitoring all cylinders for misfiring and none at all.
So if this is flex lock being the problem, where do I go from here ?

 

Flex lock up only occurs in the lower gears . During flex ,The converter partially applies between upshifts to save you fuel .
Converter shudders in most cases only occur as the converter clutch is being applied for a brief second or two . You will feel that rumble strip at 45-50 when the computer in your truck commands the torque converter to lock directly to the engine . Thats when the truck is going to shake but only for a brief second or two .

If your truck continues to shake after the converter is locked at 55 mph and above , I believe something else engine related is causing the vibes you are feeling .
I am not very familiar with OV tune , therefore I dont know how many times per millisecond OV tune is monitoring miss fires or individual cylinder injectors but that may be something to look at as well . Is there a chance you can expand the parameters for individual spark plug coils , injectors .
I have a Snap-on Triton in the shop . Its a very capable scope capable of graphing the smallest electronic glitches . It has certainly saved me a lot of grief in the past .
Unlike a dealership , when a customer brings their vehicle to me, I dont get to say its a normal characteristic of the truck
If it were my truck , I would run it by a reputable transmission shop and have one of the technicians take it for a " FREE " test drive . Test drives are always free .
This will eliminate guys like me who sit at the keyboard and try to make heads or tails of what your issue may be .
Nothing beats being there and taking the truck for a drive myself .
Transmission techs are trained to pick out issues such as yours and can usually tell just by test driving the truck what the problem is or what to try next .

 

thank you, will do. Waiting on word from 2nd dealership. Supposedly Toyota field rep is around on Thursday and they will drive another truck to see if it behaves the same ... LOL i already know what they’re gonna say. After i hear from them I will go to a transmission shop but no way in hell am I paying for something 3rd party when this should be covered under warranty BY TOYOTA. These damn service reps have basically told me that i have a 60,000 mi warranty and 100,000 mi ext warranty so to just drive the truck and if it becomes a big problem then we will eventually find out what the problem was hahaha... basically I’m screwed till the trans blows then

 

I wouldnt pay for anything third party either , however a " free " second opinion from a trained technician who has nothing to offer but his opinion and who deals with converter shudders and vibrations every day is worth its weight in gold .
In the past at Tacoma World , members have used a third party hundreds of times to gain a better grasp of whats going on with the expensive truck they just purchased .

 

MAF sensor on a 2020 needing cleaning...wtf? As far as 93 octane in these motors, mine ran noticeably worse losing performance, and fuel economy when i tried a few tankfuls. Back on 87 now...all is better. Imo, you'd need to retune the truck if running 93

 

Update: 2 dealerships have come to the consensus along with a Toyota field engineer that they are comfortable with not doing anything to my truck as they believe this is a normal characteristic.... they said they feel other trucks lag around the same speeds and that if anything was done to the vehicle, it would stay the same... this is absolute bullshit. They’re blatantly ignoring the obvious shudder im having. They said that if this is a true torque converter shudder than to keep driving as I’m covered for 60,000 miles and this will show itself more severely, eventually..

 

On today’s commute to work and back, now running 93 octane, shudder doesnt seem as bad but can be placebo. Not sure.

 

Does your 2020 truck have the latest factory tune? A buddy on mine had his trd updated, said a major difference...said its like having his ECT mode engaged all the time.

 

https://www.transmissiondigest.com/toyota-flex-lock-up-converter-a-rose-by-any-other-name/

Here's an article about Toyota's flex lock torque convertor

 

Yes

 

Thanks, read up in this a couple of days ago. Waiting to run tech stream to log solenoid activity.

 

All it's going to tell you is when they're firing...
If they were bad electrically, they should throw a code. Mechanically, they could be bad and not throw a code; those you have to remove and flow test.
Unless what you're looking to do is confirm it is flex lock.