6 hrs in KL

Arriving 4pm means the start of major traffic jams in KL, especially if its raining. I suggest you take the train, 30 mins, and RM 35 one way to KL Sentral, then take either hang around there and eat - it's an Indian quarter , or else jump on the monorail across the road and go to Bukit Bintang, 15 minutes. Don't think about buses or taxis if it looks jamamed!

Make sure you know when the last airport express train returns ;)

Last express train leaves KL Sentral at midnight. If you miss that, there may be one more KLIA Transit train a few minutes later. After that time you're stuck with a taxi, but so late in the evening traffic isn't much of a problem unless it's Friday or Saturday night.

Guess what? You are in luck!

KLIA has just organised a short tour to KL for those on transits (at least 4 hours). Check this news1 and news2 out. I'm not sure though if they have the trip for those who arrive at your time. But anyhow, it's better than none!