You could have a failing hub bearing, a slightly sticky caliper, a bad tire (swap L to right) and this goes for the rear as well.
Alignment chart will reveal a lot...as having you Toe set at maximum side of specs will allow your Z to practically drive itself on straights.
Worn parts can cause as well; not just in front...rear too.
Ensure your alignment tech starts at the rear & works forward.
Not gonna mention tire pressure or tires being of same brand, as this will cause as well.
Notice if it worsens on acceleration vs coast & braking.
Lotta things could be the culprit, hopefully you’ll find it
