Does the vehicle jerk or allow you to rev the engine while waiting for the gear to engage? After checking the transmission level you should proceed immediately back to your Hyundai dealer to have the transmission checked. It sounds like your transmission is slipping, which could require replacement, hopefully the warranty will cover it if that is the case (10 yr, 100K power train warranty I believe). You could also take it to a transmission specialty shop if the dealer trys telling you there's no problem, just for your piece of mind.
