The latest UOA for my wife's 2007 Quest shows the lead is increasing. Blackstone is recommending a 5K OCI. I have always run syn from new. I actually haven't used a dino oil since the early 1990s. PP, Amsoil and now Liqui Moly is what has been in the Quest's VQ. With such a short OCI recommendation should I switch over to PYB along with an Ultra at the next OCI for 5K and just go with it? OR...keep up with a syn like I have been doing. Cost isn't a factor as the engine only holds 4 liters. I am trying to get the lead reduced to a normal level and keep the engine clean so it lasts for a loooong time. When I look into the oil filler opening, it looks like the day I got her......clean, no varnish at all. 5K would be about 8 months or so given my wife's driving pattern.
Does anyone have any idea why the lead is up? I have a post over in the UOA section but so far no one has addressed the question as to why lead is increasing. I know there are only two samples to use for comparison but it is all the data I have. Lead is up but copper is not. It was 7 this time as well as last time. The layers of a bearing - IIRC - go from inside out as a lead / tin mix, then nickel, then a copper / lead mix and finally steel. If the bearings were wearing wouldn't copper and tin be up? Copper was the same in both samples. The tin went down in this sample from 2 to 1.
I don't use any fuel system cleaners or run any octane boosters.
Any input on either or both questions is greatly appreciated.
The Blackstone report is below for those interested.
[img:center][/img]
Does anyone have any idea why the lead is up? I have a post over in the UOA section but so far no one has addressed the question as to why lead is increasing. I know there are only two samples to use for comparison but it is all the data I have. Lead is up but copper is not. It was 7 this time as well as last time. The layers of a bearing - IIRC - go from inside out as a lead / tin mix, then nickel, then a copper / lead mix and finally steel. If the bearings were wearing wouldn't copper and tin be up? Copper was the same in both samples. The tin went down in this sample from 2 to 1.
I don't use any fuel system cleaners or run any octane boosters.
Any input on either or both questions is greatly appreciated.
The Blackstone report is below for those interested.
[img:center][/img]