Ok Ill make this short and sweet. Pros and cons does I go with the original type or aftermarket mechanical tensioner. mine is getting louder by the week.
How many miles on the engine? The chain stretches over time.
While doing a valve adjustment at 26,600 miles, my chain was slightly stretched (not enough to replace).
I prefer the OEM tensioner, no way to screw it up but if the chain is stretched, the manual may get you a couple of miles.
I'd replace the tensioner with OEM, and if still noisy, pull the valve cover, cam chain cover and check your marks for chain stretch.
If stretched, replace the chain and re-assemble..
*You can also get a good idea if you remove the stock tensioner, let it extend and see if it pushes FAR away from the block(WHICH IS GOOD-indicating the chain is in good condition.
** I personally would NOT pull the tensioner W/O pulling the side cover. There is a RISK of the chain jumping a tooth with the tensioner out...