Primacy 4 nowadays is not so much silent already.
Already got member complain of higher noise level compare to Primacy 3ST (ST means Silent Tread) after upgrading to it.
Nowadays Michelin is promoting more towards safety, as they are the best in term of wet & dry braking distance even after the tire wear out.

If want only the best silent & comfort ride tire in market now is the Yokohama Advan DB V552.

This post has been edited by littlefire: Sep 26 2019, 10:45 AM

If free go for it. If need to ask for extra money for the nitrogen gas just forget it.
Just a simple google or youtube a lot of these are just scam (Same as chamber nut change, also a scam) for tire shop to earn more money.

Our air got almost 78.09% nitrogen, so paying extra for it is no brainer.

https://www.quora.com/What-is-the-percentag...ygen-in-the-air

This post has been edited by littlefire: Sep 26 2019, 10:52 AM

FYI, there is no ST for Primacy 4
Only Primacy 3 got ST

ST = Silent Treads (Low Noise)

Primacy 4 already ditch the ST to gain better overall safety in term of braking in dry & wet situation when even new & wear out situation.

This post has been edited by littlefire: Oct 20 2020, 12:09 PM