'14 Silverado Bounces at High Speed. Not Balance Issue

[tbooth87]

Morning All,

I bought a 2014 Silverado High Country about 6 months (10,000 miles) ago. The truck had 15,000 miles on it. I noticed that when I drive 75-80 MPH on paved (not an issue on asphalt) roads, the truck bounces pretty violently. I can see the tailgate bounce probably 1-2 inches, en rhythm, as I'm driving on pavement at those speeds.

 

When I bought the truck, it had aftermarket 20" rims with some 285 Nitto All Terrains. I took the truck in to get the wheels balanced as I assumed this was the culprit. I was told that a few of the rims were slightly bent. I bought new rims last week and am still experiencing the same issue on pavement.

 

Does anybody have any idea as to what the issue might be? I just dropped a pretty penny on new wheels on Friday (today's Monday). If the truck is still bouncing as violently on pavement do y'all think I should take the new guys back and have the old ones put on?

 

Thanks,

 

TB

[silveradosid]

I would be looking for looking for one of the tires that has a weird wear pattern, no balancing can control an out of round tire. a tight ujoint can also make the rear of the truck hop

[tbooth87]

@silveradosid - thanks for the reply. I'm taking my truck in Wednesday. I've voiced my concerns to my GM dealer so I'll let you know what comes of it.

[mikedege]

If it doesn't do it at that speed on asphalt, its probably the road you are traveling on.

 

Mike

[fondupot]

If it doesn't do it at that speed on asphalt, its probably the road you are traveling on.

 

Mike

 

Yea, I'd have to agree.

[chuckl1218]

Yea, I'd have to agree.

There is a road nearby where mine hops for about a 1 mile stretch. It is a concrete based road. Happens in both lanes. Does not happen on asphalt roads or even other parts of this road. And actually is better since I installed the Bilstien shocks. Definitely the road.

[Spurshot]

Concrete roads are poured in sections. Believe it or not, the concrete is a somewhat "plastic" material. It will form pressure ridges over the years that cause this sinusoidal shape and your bouncing. I first noticed it in my 2008 on certain freeways around the LA area. Some were worse than others. In the past few years, they have been grinding the surface of the freeways in southern California. This has smoothed out the ride. Your bouncing sounds like what I've experienced in my 2008 and my 2014. The King shocks took much of it out on the highways that still haven't been ground. Part of it is the shock damping rate and some of it is the heavy unsprung weight of the truck suspension, axles, tires, wheels, etc.vs. the light weight of the rear of the truck.

[fondupot]

Concrete roads are poured in sections. Believe it or not, the concrete is a somewhat "plastic" material. It will form pressure ridges over the years that cause this sinusoidal shape and your bouncing. I first noticed it in my 2008 on certain freeways around the LA area. Some were worse than others. In the past few years, they have been grinding the surface of the freeways in southern California. This has smoothed out the ride. Your bouncing sounds like what I've experienced in my 2008 and my 2014. The King shocks took much of it out on the highways that still haven't been ground. Part of it is the shock damping rate and some of it is the heavy unsprung weight of the truck suspension, axles, tires, wheels, etc.vs. the light weight of the rear of the truck.

 

This and poor quality control with the road contractors. Why is it that the Autobahn doesn't need to be rebuilt ever 5 years? But American roads cant seem to last much longer than that. Road construction is an annuity for road contractors, just taking the tax payer money and building the cheapest road they can, because they know in 5-7 years time, they will just need to be rebuilt.

[tbooth87]

Thanks for all of the replies. Puts my mind at ease. I'm still going to have them look at any tires that may have bubbling or faults, but I appreciate the comments.

[Gofas]

I have this problem since I loaded my truck a few times.

I was tickled when I first got truck and how it sucked up the bumps and expansion cracks of our concrete roads. But I'm afraid now it bucks/ bounces bad like that. I think it's the rear leafs, jus my guess.

[dave07]

Concrete roads are poured in sections. Believe it or not, the concrete is a somewhat "plastic" material. It will form pressure ridges over the years that cause this sinusoidal shape and your bouncing. I first noticed it in my 2008 on certain freeways around the LA area. Some were worse than others. In the past few years, they have been grinding the surface of the freeways in southern California. This has smoothed out the ride. Your bouncing sounds like what I've experienced in my 2008 and my 2014. The King shocks took much of it out on the highways that still haven't been ground. Part of it is the shock damping rate and some of it is the heavy unsprung weight of the truck suspension, axles, tires, wheels, etc.vs. the light weight of the rear of the truck.

Concrete is not considered a flexible pavement, that is asphalt, concrete is a rigid pavement. What your probably seeing or feeling is a poor sub-base caused by poor drainage. The slabs will then "rock" when these voids become significant enough which is probably what you are experiencing.