I think it's the driveshaft coupler too, because it smooths out after warming up. I went to the dealer, and they said they'd have to replace the driveshaft, to the tune of $1800. Mine is a 2017 G80 AWD; is there any way to find out if the coupler can be had separate?It's the driveshaft coupler. It hardens, vibrates when not loosened up yet, then smoothes out after warming up.
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