Here is the full list of all 22 RC Rush achievements worth 1,000 gamerscore. It takes around 5-6 hours to unlock all of the achievements on Xbox One.
Won all Grand Prix.
Reached maximum level (50).
Tried, but didn't win a Grand Prix.
Explored a free roam level.
Played a Quick Race.
Unlocked all trucks.
Won a Grand Prix.
Finished first in all campaign events.
Completed the final campaign mode event 'Beat the Dev'.
Beat all campaign head to head events.
Unlocked all campaign events.
Finished a race in 2nd place.
Reached level 20.
Got your 15th level up.
Reached level 10.
Finished in 3rd place.
Finished off-podium.
Reached level 5.
Won a head to head race for the first time.
Got your first level up.
Achieved a 1st place win.
Got your R.C. racing license at the driving school.