Back in the 80's my old business partner had a buddy who was a retired GM engineer & he was wrenching for people out of his garage. He always called Pennzoil "black death." From your photos, I see exactly why!
I have heard stories like that about Quaker State but not Pennzoil. I have run it many thousand miles with no problems.
Back in the 70's and 80's we found the multi grade Quarker State would do that but not the straight weight. Pennzoil seemed to almost always wax up.
