As always, its a YMMV, but my 2 yr old inquiries for a car loan fell off right on time.
From what I have experienced, the inquiries have dropped off at the end of the month in which they were incurred, two years later.
I had something weird where two TU inquires that are due to expire this month vanished in April. Then they came back a week later. It was like they were messing with me with a mini R*.
My inquiries on TU seem to fall off a little early. Both other credit bureaus the end of the month of the inquiry.
They will fall off right on time and the ones that reach 12 months will not count toward your fico score but will remain on your report for another year.