chevyhipo

I would check my drain plug about every 1000 miles or so for the first 5000. I would not make a big deal out of this or loose any sleep over this. If any bearing shows up then take it to dealer and have them check all the rockers and fix as needed. This item will not destroy your engine. The needles are larger than the oil pick screen so they will not get in to the oil pump. Remember I am getting all my info from this forum and not GM. I read most all posting that talk about engine problems. As stated in the first post it looks like the problem started back in January and now we have some in early June reporting.

I have not read any posting about any engine blowing up or any other issues that have happened because of these rocker bearings.

I would not sell my 07 Z because of this. Remember 5 years and 100000 miles. Is this a pain? YES can we live with this? YES

This is only my opinion and has nothing to do with GM.

So lets have fun with our cars.
Henry

KGjevre

This may be nitpicking, but the thread you link to has pictures, one of which I borrowed (thanks blitzu), and you have to agree that it does not have "stock appearance" and "the HS conversion is internal to the rocker" because one can easily see the C-clips on the modified ones.





Still, this seems like an attractive option down the road.

-kg

tjwong

To the untrained eye they will have the stock appearance. I have been using the HS reman units as an option in my cam and head packages in the LS engines for the last 18 months with not one complaint

J HEBERT

Look, this is the way to go, give Randy Jr. a call at Harland Sharp and just do it

Cloaked323

Gray Ghost GS

MachAll 2005

Our engine was built 6Dec06 and car was born on 14Dec06.........First oil change at 7600 miles with no sign of needles or other significant debris. No mods, mostly hiway/road miles. I also cut the filter open and it was much cleaner than I had expected or experienced from other new engines including the LS2.

outnumbered

http://i86.photobucket.com/albums/k1...c/needles2.jpg

Does this broken rocker show that the broken portion is actually a center housing for the bearing and is separate from the rocker body itself?

If yes then with the conversion, they use the rocker and replace the separate inner piece?

Thanks

Dan

Greg Gore

Who cares about preserving the warranty to accomodate a known high failure rate item when a simple swap to more robust aftermarket parts eliminates the problem and alleviates concerns? Remember, a broken rocker arm bearing will eventually cause a broken valve spring which has the potential to take out the entire engine unless you are quick on the switch, but who is? Many continue to drive these things around with broken parts while they try to figure out what is happening.

jbp8653

1. 2007 Z06
2. 3/07 build date
3. 9900 miles when needle bearing found on drain plug
4. K&N intake, Diablo Predator tune, otherwise stock

loflyin08Z

Have any of the 2008s experienced a rocker arm bearing failure or is this a 2006/2007 problem so far?

jan eric

My build date (on the door) is 01/07. Jan eric

LGR

"Remember, a broken rocker arm bearing will eventually cause a broken valve spring" ? How does that happen?

KGjevre

I think it is a speculation as I for one could see that happen if the broken end cap parts or needle bearings got into the spring, but then on the other hand it is possible that I may have put on anywhere from just a few miles to all of the cars almost 4K miles (maybe less the 500 break-in miles when I keept the revs low) with two broken rocker arms as I have never noticed any change in engine operation or sound since new.

KGjevre

No 2008 that I am aware of.

We have 20 2007 listed here now, and there were 5 votes for issues in 2006 in this recent poll, but I am not aware of who that was as they did not support it with a post, so not listed here.

jbp8653

When the needle bearing go away the rocker will tilt on top of the valve spring producing unequal pressure on the valve stem. When this happens the cap can rock releasing the retainers. Then you really have a problem. Valve drops into cylinder and spring flies off at a high rate of speed

KGjevre

Thanks, the list has been updated with new entry and build date, and build date.

Greg Gore

It introduces a large amount of unwanted valve lash which is very hard on the valve springs. The lash causes the spring to operate minus the slow opening and closing ramps and the resulting operating shock fatigues and weakens them. I bet if you tested all your valve springs with a load tester the one that ran with a broken rocker arm would show load loss. If you continue to run springs that have lost pressure you run the risk of breaking one due to loss of valve control which is bounce on the seat and lofting over the nose at high RPM.

KGjevre

Oh greeat, more things to worry about...

Greg Gore

Not something necessarily to worry about but if you like to make excursions near the redline you do want to know all of your valve springs have at 100 pounds on the seat and 300 pounds over the nose like they were supposed to have when new. If any of the springs experienced conditions which will fatigue them the only way you would know is if you tested them and found a weak one. You wouldn't want to make 7000 RPM runs with one weak valve spring. The picture below shows what a portable spring tester looks like that can be used on the car without doing anything more than pulling the valve covers. This one costs a little over $200 but it is a pretty good one. You can get a cheapie from Moroso for about $50 that would be better than nothing. Nobody would go to this much trouble for most cars but a Z06 that can run 7000 RPM with reports of at least some valvetrain failure history should be a concern for anyone who is interested in trying to keep the original engine in the car.