Of course, even the best oil filter in the world is useless unless it has the right oil coursing through it. We've noticed that around the old trucks there are still some people (magazine editors included) that cling to the belief that conventional mineral oils are better to use than synthetic in an older engine design. That's pure horse puckey because a lot of the problems normally associated with Y-block engines were due to running the oils that were available at the time. Back in the good old days the oils were low in detergents and high in coke, which caused the tiny oil passage from the Y-block's center cam bearing to the cylinder heads to clog up with sludge and prevented oil from reaching the top end. Long story short: the results were a big helping of "Y-block charcoal surprise," that literally burned up the rocker-shafts and destroyed the engine's top end.
There are numerous synthetic and semi-synthetic oils on the market today that all do a good job to varying degrees. Choosing the right type and brand of motor oil is a topic that deserves a lot more explanation and comparison than we want to address in this article, but we will dispel one misconception about synthetic oil, starting with the most erroneous: synthetic oil is made entirely from some kind of space-age plastic instead of a mineral (petroleum) base. This is not true.
The synthetic oil that we chose to run in the 272-inch Y-block in our '56 F-100 was Royal Purple. We based our decision on what we read on Royal Purple's Web site and decided to give it a try. What intrigued us was Royal Purple's claims to reduce internal heat and engine wear (they go hand in hand), along with increasing horsepower and even lowering emissions. Immediately after pouring Royal Purple into our 272 we didn't conduct any scientific testing to verify these claims, so we don't have results that we can publish. What we can say, and will stand behind, is after we installed the genuine Ford spin-on oil filter adapter that we got from Sacramento Vintage Ford Parts and poured Royal Purple into the crankcase, the trusty old Y fired up and made a whole lot less audible mechanical noise than we thought possible. Every initial startup since has produced less bearing rattle, and the engine achieves oil pressure much sooner. That said, it's a pretty safe bet that for very little money we have increased the odds of our Y-block motor living a lot longer. That's what we call cheap insurance.