Hello again Paul,
These are two postings regarding the wind buffeting issue with the Chevy Volt. I don't have enough computer skill to forward the pictures but will try to forward the thread to you also.
Wind Buffeting Modification Photos
Just got back from the dealer where they did mods to the battery and side mirrors. There's been a number of posts on the battery enhancement so there isn't much to say except if you get it, the dealer tops off your gas tank, so you might want to keep that in mind.
The real mod I was interested in was the one to reduce wind buffeting. I live near the beach and like to drive the streets with the window down. My previous car was a roadster which I never drove with the top up, so driving around in a car with the windows up is a bit claustrophobic for me.
This modification consisted of two parts; a new "skull cap" over the mirrors and a different plastic piece at the A piller. Aero mods were made to both pieces to reduce the wind buffeting (see photos). There was no charge for this mod. Needless to say, these changes are made at the expense of aero efficiency, how much, I really won't know for some time. However, I'm happy to report that this modification greatly reduces the buffetting. I drove up to 55 mph with the driver's side window down without the buffeting noise. There was still, a tiny bit of pressure buffeting that was just barely noticable. I think this can be pretty much eliminated by cracking open other windows.
Both.jpgA Piller.jpgBoth2.jpg
GM has recently released a "kit" which modifies the side mirror housings and reduces this buffeting effect for those that like to drive with the driver's (or passengers ) window down. This buffeting is considered a normal artifact of the Volt's excellent aerodynamic signature, but it can be deemed objectionable by some. Due to a slight reduction in aerodynamic performance it MAY have a negative effect on electric range and/or fuel economy, (although I believe it to be minimal).
Included in the kit are replacement mirror bezels, door fascia, and "skull caps" (the common industry term for the outside mirror housing itself).The kit should require only an hour or so to install (both sides) however this does not include time for any painting of the skull caps if necessary.(which will obviously need to be completed prior to the actual installation of the kit)
So if this is something that you feel MUST be addressed, you can discuss it with your dealer. They will certainly find the necessary documentation if they search for the term "buffet" in their GM information systems.
HTH
WopOnTour