In put on 351 Windsor motors

[gb70]

Thanks Lynn, I was thinking of pulling a valve cover to check that. I was reading an article in Mustangs monthly last night where the builder was tearing down an original 289 that was driven mostly on the highway and not as much in town. It had over 150,000 miles and the owner had done his routine oil changes. The bottom of the valve covers were super clean as was the oil pan. I was thinking that it is most likely that the previous owners had it on the highways more than the city. If it was taken care of as much as the rest of the coach it should help my engine life. I have never had a 351W before. I think for my next oil change I will drain a quart and add a quart of oil cleaner additive and run it warm for 5 minutes. That should help free up any sludge it may also have.

What brand oil do you suggest may be best here for this application?