While Steve Coppell's side were classy and incisive and pounced on some threadbare home defending, Crewe offered a real threat up front where Luke Rodgers was outstanding.
Rodgers' fierce drive in the 14th minute helped put the Railwaymen in front as Marcus Hahnemann failed to hold the ball and Lee Bell finished off from close range.
But Reading, who had already hit the post through Kevin Doyle, were soon in control of the game.
Nicky Shorey bent his 24th-minute kick around a flimsy-looking wall and while home keeper Ross Turnbull got his hands to the ball he could only help it in at his near post.
And the keeper was picking the ball out of the net again two minutes later when Glen Little arced a deep cross to the back stick and Steve Sidwell looped a header over the flapping Turnbull.
Two minutes before the break he was beaten for the third time when Leroy Lita spun away from Steve Foster and fired into the bottom corner.
But Crewe refused to throw in the towel and had a real go at the leaders after the break.
Rodgers fired just past the far post before Gareth Taylor grabbed his first goal since joining on loan from Nottingham Forest.
Kenny Lunt's cross was headed on by Steve Jones and when Hahnemann could only push it weakly out, Taylor followed up and blasted into the top corner in the 50th minute.
But Reading restored their two-goal advantage within two minutes with Lita getting his second when he guided the dangerous Bobby Convey's cross in at the near post.
Doyle should have wrapped it up when he broke clean through only to drag his effort wide.
And that could have been costly as Crewe pulled another back after Shorey handled Steve Jones' right-wing delivery.
Lunt stepped up to despatch a low spot kick home with 22 minutes left, but was then sent off in stoppage time for a late tackle on substitute Stephen Hunt as he the midfielder charged through outside the box.