Torque converter shudder?

Hello I just purchased a 2017 with 50k miles. I have noticed that right around 40-45mph I get this very slight but noticeable surging feeling. After some reading on here it seems like the “rumble strip” sensation caused by the TQ. My sensation is very light and nothing like a lot of people on here describe. I did the brake tap test and S4 and I think it stops the sensation for a few seconds.

the truck had all service done at Toyota but all it’s had are oil changes and tire rotations for the first 50k miles. Since I got the 4Runner I have changed all the diff oil, transfer case, coolant and brake fluid and greased the driveshaft. I also did a transmission drain and fill and the fluid looked ok. A little dark but no burnt smell.

I also did a stall test in drive and reverse and I stall at around 2200rpm. Does anyone know what the actual stall speed is supposed to be?

I’d like to get ahead of this shudder. Should I do another drain and fill? I replaced about 3.5 quarts on the first drain and fill. Should I add some shudder fix?

thanks for any help.

 

I would replace the fluid a couple more times, OEM fluid and make sure you have the levels perfect. Don't base it on amount that drained out-do the correct method by temperature.

 

hi thanks for the reply. I did do the at temp check method outlined in the service manual. I tried a few times before actually changing the fluid to make sure I could do it.

I will try another drain and fill this weekend and see what happens.

 

I replaced the fluid on mine at 58K (I guess recommended is 5yrs or 60K). In any event, I noticed at first uhm...not sure how to describe but like slipage or hesitation when starting from cold. My case might be a bit unusual but coming out of my neighborhood, I need to get on a road that you got to do 40 to 50 pretty quickly and so when the tranny is cold it doesn't like to shift right away. But once it is up to temperature and I'm cruising around town and warm, I don't feel any issues. So maybe give it sometime because during the first flush, you actually removed a good amount of junk/metal type material and new fluid takes a little time to get homegenous in the system. I wouldn't be too concern either with the low miles you have so far. My 2c. Good luck.

 

It could be the beginning of the rare shudder/chatter. A known problem with our A750 tranny. Its the Toyota FlexLock torque converter lock up system. Controlled in tranny valve body. Lots of posts on this topic for many years.
Does your runner do this in "D" at light throttle?
If you drive same road in S4 instead of "D" does it NOT act up?

 

yes but only very lightly at like 42mph. Goes away in s4

 

When Flexlock malfunctions the lock-up clutch plates in the torque converter fail to release timely and these friction linings act as momentarty brake.
I wound up with a new tranny at 48,000 miles to basically fix the defective tranny valve body components.
See screen shots of some of my on-line reading while my 2017 was suffering this shudder drivability problem.

 

Great info. Seems like at that mileage it would be a manufacturing issue or early part failure.

 

I found shudder TSB for models of Toyota vehicles back to 2007 on-line. Same Flex lock issue.
Yes, mine was covered/paid by Toyota. Their first incorrect repair was $3000, second correct repair was $5000. So $8 grand for a tiny component inside valve body or valve body itself. Probably a mfg error by Toyota or a supplier. A member put an additive into their tranny and it helped drivability but maybe masked real issue.