Jim, I don't want you thinking I am trying to throw you under the bus here. We have a long history of that and I am not the least bit interested in it, It is bad for everyone one involved when it happens. I only posted because I saw that you were having issues and were not happy with Morels lifters. I am only wanting to shed light on these issues and offer what I have learned about these lifters. Looking at the box those lifters came in the part# is SL540 correct? You referenced TA's part# above and I noticed after you posted pictures of your boxes that the labels didn't look the same as TA's so I did a little research and digging because I am very familiar with the Morel lifters, oil spec etc. I know that these lifters are very specific to the oil they require by design not by lifter bore clearances although they do have to be with in spec bore wise just like any other lifter. I can assure you that your lifters are mislabeled. 5W40 is for the Hi rev lifters on which they don't make for our old iron 455's, I posted a pic below to show what the sticker from a Morel box that was labelled by Morel for there hi rev lifters, as well as the labels on the TA box of the lifters in question. When I showed my Morel dealer the pictures you posted he told me that they were PBM SL540 but the oil sticker is not Morels hence the picture below that he e-mailed me, and he also reconfirmed that the lifters in question do require the thicker as in oil so in regard to the mislabeling I guess it is a mystery. I can tell you by design 5W40 is not recommend in that lifter and that could very well be the reason you are having noisy lifter issues. I specifically run a 50/50 mix of 10W30 and 15W50 JG hot rod oil and that is why I researched these the first time I used them to make sure they would suit my needs. The reason I was asking about the wheel is because I believe the Morels that TA sells is the only hyd roller lifter that has a live axle vs swedge type. That is why I was curious to see what the Johnson's had because the swedged design is ok for more milder cam profiles The problem is the aftermarket uses profiles based on .750” wheel and Putting a .700” wheel on one of these lobes increases intensity and the lifter can loose contact with the lobe profile. Once this happens the wheel begins to bounce the swedge design axle can “walk” out of lifter causing catastrophic failure. In my opinion like a good quality solid lifter a good quality HYD lifter should have a live axle also.
Joe Gibbs HR-2 10W/30 Conventional oil for the first 2 years, then I switched over to the HR-4 synthetic 10W/30. No difference at all in noise. Even when I had these heads on my other block, they get clicky when hot. The only time I even notice it is when the hood is raised. I can't hear it at all driving down the road. Not that big a deal to me. I just wanted to make sure the lifters were OK.
Next oil change try a 50/50 mix of 10W30 and 15W50 JG hot rod oil, your bearing clearances should be ok for that weight.
