I posted a UOA recently and a comment was made about the high lead level. In my post I stated I had installed a dual filter and by-pass just after the UOA. A suggestion was made that it may have been better to hold on the dual by-pass until I got the lead levels down. So does the installation of extremely high filtration inhibit accurate UOA's? If extra wear partilces are being trapped they're not being measured in the UOA? If I am trying to analyse oil is it best to try and let the oil do it's work and not the filtration? With that in mind would it be better to have minimal filtration so that a problem could be found quicker as it would register faster on a UOA?