What should be the correct preload on the lifter? I heard 40-60 thousands.

 

WCCH recommends .040 to .080, with .060 being optimal

 

this might be a dumb question. But are you SURE its not a blown header gasket? If the gaskets just ripped a little bit you probably wouldn't here it just idleing with the hood up. But when you get in your truck and take off its pushing the exhaust gasses harder causing that annoying ticking.

 

I run the GT7 cam in my 5.3 and it is quiet as stock valve train.I purchased complete kit from Lingenfelter with Comp 7.4 pushrods and Yellow LS6 SPRINGS.

 

What is the cadence of the noise? Can you discern if it is coming from all cylinders or a single cylinder? Have you narrowed it down to Bank1 or Bank2? Is the sound intermittent or constant? The only time I've been able to hear injector pulses(over other mechanical sounds) is with a mechanical stethoscope.

 

My PAC springs are noisy as hell, but I don't have much, if any firewall insulation.

 

I've heard .060 to .090, but I've heard tons of other opinions, so who knows which preload is correct. It's not a blown header gasket because I changed it when I swapped the lifter. Plus it ticks at idle. It really sounds like its coming from cylinder 7, which is where that pushrod with the extra wear came from...exhaust valve. But replacing the lifter did nothing. The sound is definitely consistent... Sounds too slow to be anything rotational like a flywheel, but seems just right for a pushrod to be flying off the lifter for a split second...
I am going to install the 7.425 rods when they get here, like viciousknid said.

 

Have you removed the rocker arm from the pushrod with wear to inspect it for wear or missing needle bearings?

 

I did check all the rockers when I pulled the head...no wear of any kind. New pushrods should be here today and I will install either friday or saturday...

 

What pushrods are you using Worktruc?

Anassix. Do you have DOD and did you change your lifters? I just realized you are an 08 and if you have DOD I recall that you have to change the lifters.