How can I tell if my timing chain needs to be replaced??

 

How many miles are on it? How do the teeth look on the timing gears? How much slack does the chain have?

 

I haven't checked yet but I'm changing out my opti so should I go ahead and check it anyways to be on the safe side

 

They aren't terribly expensive, however you do have to drop the front of the oil pan to get the timing cover off and risk damaging the oil pan gasket. That too can easily be fixed by strategically placing sealant on the block, pan and w/in the newly formed cracks of the gasket before bolting the pan up.
Nothing is ever easy.
How many miles on the engine/timing chain? Any modifications?

 

It just turned over to 140,000 and I have a k&n cai,trick flow elbow,msd wires,ngk tr55 plugs,computer tune,3:73 gears,3 inch catback,slp 160 thermostat

 

At 140k, I would put serious consideration into changing the timing set while you have things apart. Also all timing cover seals while you're at it.