2010 Lacrosse - Rear windows down only issue

preacherman2

I have the 2010 lacrosse CX. I like it, except for loud tire road noise. But my question is, has any one noticed that if you put only the rear windows down while driving, how badly the car vibrates. Maybe this is common, I've not asked the dealer about it.

e_net_rider

I believe this is mentioned in owners manual. The car should not be vibrating, but the air is cavitating causing a very annoying sound at highway speeds. This is due to aerodynamics of the vehicle and this is not the only vehicle that will display this phenomenon.

preacherman2

Thanks for the response.
Question. Has anyone noticed a brand of tire that produces less road noise? I have the michelin mxm4

e_net_rider

That tire is the standard for many Buicks.
And on the Lacrosse is much quieter than the GY. The GY is so noisy I considered having my CXS Ziebarted for noise deadening. The GY seems to only show up if you get Touring Package. The CXS is supposed to be quieter because of the hyperstruts used on the front. Yet my CXS is much noisier than a CXL. Got to be the tires, right?
But as to whether this model of Michelin is noisy, I have no real comparison. What I can say is the Regal, same model of tire, is much noisier than the 09 Malibu LT2 I had, which had lowly Firestone FR710 as I recall. They easily broke loose when cornering, wet surface. Also the Malibu was apparently designed to be quiet where as the Regal was aimed at the crowd that likes noises, especially noisy exhaust.

preacherman2

Thanks for the reply.
I'm drive the CX, which has the 17" wheels. Since one of the selling features was the quiet ride, I would've thought the tire noice would've been less then it is. Not overly complaining, just expressing my thoughts.

e_net_rider

I have to agree on noise.
It seems that they are actually moving away from comfort in many areas. Example, steering wheel. Older vehicles had a rubberized fabric device in the steering shaft before reaching the power steering unit. It was called a coupler, but was actually a de-coupler, an isolator for all those annoying vibrations and noises conducted to the steering wheel. Has GM not heard of carpal tunnel or other problems created by such?
And rake designs of columns are not near as comfortable as a true tilt.
I guess I am complaining.
I have learned that whatever supports the bottom of the seat is springy. That is I actually bounce on it with the bumps. Very little padding. Sort of like riding on an old horse drawn wagon where they used double leaf springs to absorb some of the jolts. That was before the day of shock absorbers giving a pretty good bounce. That seems to be the design of these seats, and it does not seem to matter whether you have the cooled seats or not. It seems they used the same seat for both, in leather at least.