I purchased a new 2008 Suburban 2500 2WD 6.0L three months ago. When pulling our Airstream trailer there isa loud, high-pitchsqueaking sound from the rear liftglass. It only happens at freeway speeds and only when pulling our trailer. I suspect that the turbulence between the rear of the Suburban and the trailer is causingthe liftglass to rise up and we get the resultingwhistling windnoise.

Itook my Suburban to the local Chevy dealer today regarding the noise problem. When I told theService Advisorabout the issue, he responded that "it sounds like an Airstream problem to me." Then I took out my small, hand-held digital tape recorder and played the noise for him. His response was "yeah, I guess you can't just turn up your radio for that one."I got a call from him late this afternoon saying they couldn't duplicate the problem. I again told him that it only happens when towing. His response was "yeah, you have the evidence on tape. We're going to keep your car overnight and talk to the engineers back East tomorrow. They may have a solution for us."

Has anyone else experienced this problem?

 

When searching the internet I came across a GM bulletin entitled "Windnoise from Rear of Vehicle/Liftgate Glass." It is Technical Service Bulletin #06-08-66-012C and was issued on July 31, 2007. It states the following condition: "Some customers may comment on excessive windnoise coming from the rear of the vehicle, expecially when trailering."

The correction as noted in the bulletin is to (1) replace seal, (2) replace stop bumpers and (3) replace rear glass. A liftgate latch adjustment may also be necessary.

I called my dealer with the info this morning. They pulled the bulletin up on their system and ordered all of the parts for my Suburban. The rear glass has to come from Michigan by ground transportation due to its size. It is supposed to come in sometime next week.

I'll post again after they have done the work and let you know the result.