this is the third 2.5 i have owned. one was bought new with 13 miles on it and sold with 120000. no noise. the other is beat on HARD by a friend who wants it to blow so he can swap it out. 2 seasons, no noise, yet. the tick in mine is worse after warm up, when the oil thins out, but you can hear it always. between gears if you over-rev some it sounds like the valves float. with a stethescope you can hear the lash (tick) in cyl 3&4 mostly 4. it seems that oil potions can do one or more of three things, thin oil, thicken oil, clean sludge deposits. it dosen't make sense that it could thicken oil and dissolve sludge at the same time. and if it thins the oil more than when it is hot the noise would be worse. most of these i have seen are not ment to be driven with or left in the motor for an extended period. my piont is, my lifters are new. and if they are pumped up properly they are getting good oil flow. the lash (noise-tick) has to be somewhere right? i didn't notice any abnormal wear on the rockers or pushrods. i didn't really inspect the valve stem tops or go any further that day because i expected the lifter swap to take care of it, i was mistaken. in my opinion there has to be wear-lash some where or possibly weak springs. but if the new lifters are not pumped up when i pull them tomorrow then can i assume there is a restriction or a flow problem? thanks for any input
