Head noise

I was looking at purchasing a 2011 tundra 5.7 , on the test drive I notice a ticky rattle from passenger side head , sounds like front half . It's not injector noise . Are these known for chain issues or lifter issues . Deffenitaly not exhaust shield or external , it goes away with revs and is more prominent when warm . Not crazy loud can barely hear it over the obnoxious injectors. Should I buy it , is this out of the ordinary?

 

These are known to have a noisy valve train. But you say you can only hear it on part of the engine? It’s not impossible that the timing chain tensioner could be going out. Have them throw in an extended warranty. Or pass if you’re not feeling it. Drive a few others so you can compare.

 

I'm not feeling good about this one might have to pass