Spieth won The Open at Royal Birkdale last month with a memorable back-nine, adding to his Masters and US Open triumphs from 2015.
The 24-year-old is now looking to emulate Gene Sarazen, Ben Hogan, Gary Player, Jack Nicklaus and Tiger Woods in making it a clean sweep, though he insists that the growing expectation levels will not weigh him down at Quail Hollow.
"This is a Major championship, this is one of the four pivotal weeks of the year that we focus on so there will certainly be pressure, but I'm simply stating there won't be added expectations or pressure," he told reporters. "I just don't feel it. It's not a burning desire to have to be the youngest to do something, and that would be the only reason there would be added expectations.
"If I don't win a PGA in the next 10 years, then maybe there's added pressure then, and hopefully we don't have to have this conversation in 10 years. But if we do, then it might be different. But it was only two weeks ago that I was able to get the third leg, and that's so fresh in my mind.
"I'm happy that I can't add pressure to this week. I'm free-rolling, and it feels good. I'm about as free and relaxed at a major than I think I've ever felt. Expectations? I really don't feel any. This is a chance to complete the career Grand Slam so I'm going to go ahead and try. But I believe I'm going to have plenty of chances, and I'm young enough to believe in my abilities that it will happen at some point.
"Do I have to be the youngest? No, I don't feel that kind of pressure. Would it be really cool? Absolutely, and I don't come to a tournament unless I plan on giving it my all in preparation to have a chance and to ultimately close a tournament out. I recognise where we are and what it would mean to win a major, not anything else other than that."
Woods is currently the youngest player to have achieved the feat, doing so when four months shy of his 25th birthday.