2.5 pro comp lift issue

I have a 2012 access cab with 2.5 pro comp lift and 285/65/18. Man at highway speeds 75mph (120kmh) the passenger seat starts shaking and shaking quite violently. It is so annoying. Anyone know a easy fix?

 

Sounds like your rear tires need balancing...usually vibes in the seat its the rear tires and vibes in the steering wheel are the front tires. I would first check the balance then go from there and look over everything you did to the truck when installing the lift. Could be a lot of things causing the vibrations.

 

I just had them all balanced and it is still shaking... lift looks fine too me, i am no expert though. Do you know if you need a diff drop for a 2.5 or 3 inch lift?

 

had an alignment recently. had a hell of a shimmy in the steering wheel so got the tires balanced. unless they just did the front and not the back.

 

Maybe get your wheels rebalanced at another shop. Other than that check suspension have someone shake/move up and down on your truck and get under the car to see if everything is tight

 

i will give that a try