Why didn't you take a video "the rear pinion screaming "? The techs at dealerships rarely want to look at the car unless it has a code. No code - no problem. Things like these need to be recorded.
I had to deal with that, where driver's door was rattling, and taking the drive with foreman - he couldn't hear. Only after I took a video recording were they convinced. Turned out - a lose screw in the door. Noise gone.
|