I did the same thing when I traded my caps. Just in case.
RE: you comment above about planned obsolescence and the transmissions, I have a different view. I think they tout their life-long transmission fluid for the female customer. My wife can check the oil in her car, no problem but transmission fluid?....no way. So they make it a selling feature so their female customers aren't intimidated. There's a lot of this that goes on in the car business, heck, in MOST businesses....all geared to capturing the female customer. It's a great marketing strategy, but not always a good design/engineering strategy. Do most cars REALLY need a flip down mirror on BOTH sunvisors? Probably not. Oversize buttons on the radio and other accessories? .... better access than small buttons if you have long fingernails. Same with outside door handles. On the 06 models there is no cup in the interior arm rests to grab the door to close it....just the handle mounted too low on the door and totally unintuitive. But it's less abrasive to grab a handle than stick you fingers into the cup to close the door. Fortunately, they corrected this design flaw in the next few model years. And the anemic heat coming out of the floor vent?... Yep, you guessed it. My wife used to complain about the amount of heat that came out of the floor vent in my Mustang a few years back. It had a great heater that flowed a lot of air out of the floor vents. But she never complains about the Explorer's floor heat. Instead, she complains about the noise of the fan when I replaced the factory one with an aftermarket one that, according to her, sounded like a jet engine. I never noticed a difference.
I have no problem whatsoever with them building their products to accommodate the widest customer base possible. Good for business and good for the economy. Just doesn't always translate into the best product, IMO.
Okay, sorry for the off-topic stuff. Lower pressure radiator caps....good choice. Waiting to see what the temp difference is this summer between the 20 and the 16.