Thank you so much guys.
Originally Posted By: skyship
The engines that seem to suffer increased wear are in three basic groups, firstly the old classic car blocks the were designed back in the days when most engine oil had lots of Zinc, secondly the flat tappet engines that were rebuilt using poor quality steel components (They had some real big issues with running in if a high Zinc break in oil was not used, but also needed about 1200 ppm after break in) and thirdly there have been some modern lemon blocks, mostly from VW that started to suffer from increased wear when the Zinc levels were cut below 1000 ppm due to Cat and EGR related restrictions. The recent further cuts due to DPF restrictions have further reduced the Zinc levels and if you don't have a DPF it's a good idea to steer clear of C3 rated oils, regardless of all the publicity.
by DPF you mean Diesel particulate filter? My cars I mentioned have petrol engines, I guess they don't have DPF but they have three way catalytic converter.
As far as I understand it is safe to use SN grades in most 80s and 90s cars, only it should not be c3 rated, correct me if I'm wrong.
I also asked Penrite about older engines and they said they generally mean 1970s when they refer to older engines.