I am looking into aftermarket expansion tank options to get rid of this ugly tank and hopefully clear up some room for a better air filter option on my turbo 4.8. What is the stock cap pressure on these GMT900 trucks. I’m seeing 20 psi some places and 15 psi in others. Bought my truck used and my cap does not have the pressure listed on it. Nor do I trust the previous owner considering it doesn’t fit properly.

Thanks buddy