Ppickett21, what are your cues to ask him to run?
When you ask him to run (run or lope?), do you keep the reins loose or not? What kind of bit do you use? If you use a shank bit and tend to ride with a tight or otherwise not loose rein and ask the horse to go faster than a trot at either a lope or a run.....then you may be causing the crow hopping. Especially if you grip with your legs.
How balanced a rider are you? Do you tend to lean forward or back? Do you bounce in the saddle? Or do you move with the horse?
Also....you have had him since February....have you ridden him steadily since then? When you first got him, did the sellers ride him at all speeds? Did they have any trouble?