I noticed a vibration at speeds near and over 80 mph. i took it to the vw dealer where i had purchased and they found the bolts where the driver front axle connects to the transmission output shaft were loose and backing out. they replaced the bolts, but i'm still having vibration in the driveline. i'm worried what other bolts may be loose or what associated parts may have been compromised as this is potentially a very dangerous safety situation for myself and anyone near my vehicle were the axle to come apart at speed.