Timing Chain replacement?

My 1996 S10, 2.2, 5 speed, 2wd just turned over 140,000 miles. I have owned this truck for almost 10 years and it had about 60k on it when I bought it. I am quite certain the timing chain has never been replaced and I have always heard you should replace them after the vehicle hits 100k miles. Am I flirting with disaster by not changing the timing chain? Everything else runs/operates smoothly, I change the oil every 3000-4000 miles, and take pretty good care of the vehicle.

Forgive me if this question has already been discussed, but I couldn't find it anywhere in the archives of this board. Thanks for any advice from other S10 owners with any experience in this.