I have an a4b7 07 plate. It shakes like hell as you increase speed, I’ve changed tyres, tracking done, balancing, checked wheels for buckling, bearings seem ok, anyone got any suggestions, could it be engine mounts?
failing or failed engine mounts will be more apparent under any load situation , hence acceration etc.
just cruising at constant speed or gentle driving and the amount of engine movement will be a lot less hence less vibrations .
High milage cars are very prone to leaking mounts and they will need replacing, also check the snub mount and rear mount as well past the best side mounts will put more stress on the snub and rear mounts so all 4 maybe due for replacement.
Just get under the car and look up at both side mounts, any staining on the lower sections will indicate failing unit.
had a really bad passenger side one that had dropped a lot and engine was very rough.