Onstar Upgrade/Humming and Vibration at higher speeds

[obis88]

Just had my Onstar upgraded to digital yesterday at the dealership. Has anyone else had to have that upgraded? They said my 2004 GXP had an analog system and that I needed to upgrade if I still wanted it to be functional. Cost me $200. I noticed when I went to hit the Onstar nothing happened! So I went to the dealer and they explained that to me. But just curious if all the 2004 Pontiacs had the analog ONSTAR system?

I have another question. When I had my GXP in Germany and was driving on the autobahn, I had no problems running the car at 120 mph with the cruise control on. Ran like a charm. When I got back to the U.S. we drove all over the country for 2 months and out west I was able to "open her up" to about 120 at spurts where there were no ther cars and it was dry and safely done. No problems. But last week I opened it up on a long bridge early in the morning with no other cars around and at 125 I heard this humming noise that got louder! I let off on the gas immediately and it slowly went away as the car got down to about 90 mph. I tried it again and it happened once more. I thought maybe it was the tranny but the Pontiac transmission guy said he doesn't think it was the transmission. The car shifts normally during city driving and runs beautifully at 65 mph with no probs. Just when I open it up at the high speeds does this humming and vibration occur. What else could be causing this? Wheel hubs or bearings? Has anyone else experienced this?

[Rye Guy]

My 2004 had to be updated as well. I also had to pay the $200 to upgrade. The upgraded antenna does not stick to the window very well. It was coming off twice. Both times they replaced the full antenna. And now it is starting to come off the window again!

I used to have vibration in my car at 100 kmph but the wheels just needed to be rebalanced. Apparently they didnt do that very well at the factory. I didnt have any humming. Sounds like a wheel bearing to me. Keep us informed.

[GXP Venom]

Some 2004, most 2005, and all 2006 and newer model-year GM vehicles with OnStar are equipped with dual-mode (analog/digital) equipment, guess the Bonnevilles were 2005. Obis did you check to see if either front tire has the tell tale sign of a taped wheel weight missing? Some half the sticky stuff is left, some show a shiny strip of metal were it used to be. Might be all thats wrong. Wouldnt hurt to check your end links and sway bar bushings as well. My bushings are looking beat, maybe my air ride's fault. Or all the torque under nitrous?

[2.3 turbocoupe]

At 38k miles, my GXP had a faint humming coming from the right front passenger side. I was hearing it mostly at 30 - 40 mph. My daughter could not hear a thing, but I kept hearing it. Per the dealer, it was the right front wheel bearing, and I think they said they had to replace the entire hub assembly.