Vibrations in the seat at 38+ mph

Stiffler · August 31, 2023

I have a vibration that i mostly feel in the seat at around 40 and up. Strange thing is some days its better than others but its been there a while. I've got newer toyo at3 tires stock size p rated that were just rebalanced a few days ago. Also i have an 1 in block lift with 5100 bilstein shocks. Vibrations seems to have started around 2000 miles ago Have any of you experienced this or have any suggestions on what to trouble shoot? Im thinking its the rear because I dont feel it in the steering wheel.

2020 rst 5.3 8 speed

Edited August 31, 2023 by Stiffler

swathdiver · September 1, 2023

If you rotate the tires and the vibration stays in the seat you've eliminated the tires. Checked the rear brakes recently? How about the u-joints on the driveshaft?

Did you replace your u-bolts when you installed the lift block? I know people reuse them but I come from working on big rigs and that was a no no. We always used new u-bolts as we saw the carnage from those that tried to get away with not replacing them.

Stiffler · September 1, 2023

Thank you for the reply, The brakes should be in good shape I only have 20K on the truck. The U-bolts were new but i'm ordering a new set just for peace of mind. I'm going to swap tires this evening and try it. If that don't make a difference i guess i will take the block out and try it. I think i can get away reusing stock U-bolts for that just to trouble shoot and order new bolts accordingly. I wouldn't think that would change the angle enough to cause the vibration but I could be wrong. Could the transmission cause a vibration like that.

GMCustomerService · September 18, 2023

On 8/31/2023 at 4:23 PM, Stiffler said:

I have a vibration that i mostly feel in the seat at around 40 and up. Strange thing is some days its better than others but its been there a while. I've got newer toyo at3 tires stock size p rated that were just rebalanced a few days ago. Also i have an 1 in block lift with 5100 bilstein shocks. Vibrations seems to have started around 2000 miles ago Have any of you experienced this or have any suggestions on what to trouble shoot? Im thinking its the rear because I dont feel it in the steering wheel.

2020 rst 5.3 8 speed

This is certainly not what we like to hear, Stiffler. Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with the vibration on your 2020 Chevrolet Silverado's seats. To do so, please send an email to [email protected] with ATTN: Stiffler/GM Trucks in the subject line.

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