2018 Tundra Vibration

Hi guys, hoping someone can help me. I have a 2018 Tundra Dbl cab 4X4 SR5 with 4.6 liter engine, stock 20" wheels.
Since new I have had a vibration in my seat at speeds between 40 - 55mph. Only when I am in overdrive and engine tach is around 1100 rpm and I am just feathering the gas to maintain speed. It feels like someone is shaking my seat. If I speed up or take foot off gas it goes away.
To date it has been back to the dealer 3 times.
First time they said transmission fluid was low. ??? Was brand new.
Second trip they told me tires out of balance and they balanced them.
Third trip they were told by Toyota to Road Force Balance tires.
At this point truck just turning 8k miles and I still have the vibration.

Any help or ideas would be appreciated. Thanks

 

Trade it in

 

Welcome from Colorado. Have a reliable 2nd party check it out besides the dealer.

 

Isn’t there something called a lemon law?

 

When they balanced did they rotate tires to see if source of vibration changed?

 

Might be worth contacting Toyota corp and try a different dealer.

 

Sounds like torque converter is locked up and feathering the gas isn’t enough to disengage it to allow it to downshift properly. That’s not an issue. That’s just nature of the beast.

 

I am not sure.

 

Thats a good possibility. Thanks

 

Lemon law is very difficult to go through, speaking from experience. My recommendation would be to contact Toyota regarding the issue and seek their guidance. It may be as simple as visiting a different dealer.

https://www.youtube.com/watch?v=wZM30NvejbU - another possibility!

 

I fought this with a 2010 Nissan Titan and never could figure it out. Same symptoms as you too. I replaced the rear shocks, shimmed the axle (to adjust pinion angle), road forced balanced the tires, and replaced the u-joints( even drove without a front driveshaft to see if that was it. ) But nothing ever fixed it and the entire rear would still vibrate. The only other thing I could think of is maybe shackles or torque converter as mentioned above.

 

Check the parking brake mechanism under the rear seat on the driver side. Mine was corroded badly and binding and not completely releasing the e-brake. I had taken it in and the dealer could not find it. I just happened to feel the rims after the vibration (same started at 45 up to 55-60. No shake in the steering. the drivers rear rim was really hot and the other 3 were not. I found a post on the issue and it advised to lube the parking brake mechanism. I lubed the parking brake mechanism and it stopped. It did come back the next year and I dug in and really cleaned it and oiled it and now I do it once per year. I also spray the underside with fluid film and load up the parking brake mechanism. When you see it you will understand how it can bind up especially if corroded. (you don't have your location in your sig so not sure if in a rust belt area). Anyway, Something to check. Dealer had no clue. First check your rim temps after driving for a while.

 

If anyone else has this problem call Toyota and open a case. This is bullshit. I didn't buy a $40k truck to have it vibrate at 50 mph and they tell me it's the characteristics of the transmission.