I was going to put sylicone around the rear cover seal for reassurance. It wasn't leaking before, but I had my truck apart for about a month so I wanted to be sure since I can't remove my engine. Every other engine gasket I'm changing out though.
I'm in the long process of headstuds. Since I had a high pressure oil leak I thought this was the perfect time to do it.

 

About 1500 miles on my rebuild with the shorter pushrods. No issues thus far. Would like to be able to give you more data but it's being traded in tomorrow.

 

While I would agree with you, my engine experienced none of these possible causes with a lifter failure.

 

My theory is still unproven and I am having a hard time getting any data from people.
But here it is for you to think on. I have heard that the lifters that tend to go first are
the ones in the back of the engine. That also happens to be the end of the oil gallery
for the lifters.

This is one of the things my theory is based on. Some small block builders that have
the same dead end oil gallery like we do will plumb in extra lot lines to the back of the
oil gallery just to help keep up oil pressure back at the last lifters.

This is the reason I ask when people say that they had a failed lifter where the location
of it was and how did it fail.

I have been thinking of a way to get more ill to the back of the oil gallery and I think it
can be done with some custom plumbing sort of like the regulated return for the fuel in
the heads. The problem will be getting to the back of the oil gallery. There is not a of
clearance between the back cover and the block for lines to go in and I can do what the
small block builders do and take it down the valley. Reason being is that we seem to have
a few things in the way. HPOP it's reservoir and the turbo pedestal mount location.

Sean

 

It seems in most cases it is one of the rear 8 that fail.

 

I wonder if synthetic oil is better for them.
And whether 15w vs 5w is better.

 

Mine was front lifter and was running Motorcraft 15W/40 Semi synthetic since birth.

 

run6.0run, If your going after an oil leak at the same time then it all makes sense.
As far as which lifters fail, I've seen them go on each lobe of the camshaft but it only takes one!
We did tear down a core one time that had lost 12 lifters with 12 lobes destroyed on the camshaft. I don't know how the guy kept it running as long as he did.

 

I haven't researched but I understand these particular lifters are relatively common (by part #) and even have a SB Chevy application. If that is in fact correct, it seems stepping up to a set of quality aftermarket performance lifters might be worth the bucks, especially if you're in there already, given how much headache and expense is involved with a cam change. Factory spec parts can sometimes be less than impressive. I've seen a couple of HPOP's that are cast so poorly they look like a potato someone machined. The quality of the raw materials is also suspect in my mind. Evidenced by the thick shedding layers of corrosion on some engine blocks, and cracking (or micro cracking) on many cylinder heads. Recycling is a "no brainier" for conserving natural resources, cost reduction, and reducing pollution, but I suspect high levels of copper and other minerals in much of the recycled iron available today is serving up sub-par parts, even if the manufacturer does a good job. General observation, not talking specifically about Ford stuff. Many of the parts sold as "high performance" mention the quality of the raw materials. I'm not in that industry but I have read different "spec'd" raw materials are available at different prices.

 

Well, just pulled out the lifters and they looked perfect. Unfortunately I drop one while I was taking it out with the magnet.

So I'm just going to install the new front two sets. They are also different plastic retainers than stock too but they look the same as stock lifters. Is there any procedure you have to do before setting them in? Do you need to pump it with oil?
Also there is a hole on the side of each lifter (I think to let oil flow through it), do they need to be facing a certain way (to front or rear)?

 

Drop it in a cup of CLEAN FRESH oil that you use and let it sit for a bit.

Sean

 

I put the holes in the lifters all facing forward. It doesn't matter which way they face, I just figured if a guy were to face them some way forward would be best to get all the air out of the lifter recess (motor has slight tilt back, air should travel to the front).

 

If there is enough oil to keep the lifters pumped up there should be enough to lube the rollers. I blame the failures on the double load each lifter has (dual valves/springs per lifter). The 6.0 is the only motor these lifters are used in that have two valves per lifter. These are the same lifters used in 7.3, chevy, chryslers, and others.