Hey guys, trucks been down for a week. Ive put 3000 miles on the new engine with no unusual noises and good oil pressure. I drove the truck to walmart and back which put about 60 miles on it that day, parked it for 2-3 hours, jumped in it to go home then TAP TAP TAP TAP TAP TAP TAP TAP!!! As soon as i heard it i shut it down. Then i thought "MY ENGINE IS F@%$&D!"

So far ive done this.
- checked all the valvesprings, pushrods, rocker arms.
- started the truck and unplugged the coils one by one.
- unplugged all coils and injectors, turned engine over but couldnt hear anything.
- you cant feel the tap through the engine by putting your hand on it.
- can feel the tapping on the bellhousing.
- started the truck put it in gear, no difference in noise.
Ive searched the forums and youtube and nothing quite like what i have going on. Now im 50/50 on screwed up ls7 lifters or flexplate/converter.
Friday the truck is going to san antonio to get the trans swapped out with one from RPM transmissions along with the 3600 stall. If there isnt a cracked flexplate, then i guess its a lifter.

Anyways just seeing if you guys experienced anything like this or know something i might have missed.
Thanks.

 

Any way you can post a video of the noise?

 

I had a lifter ruin a lobe on the cam, it was the closest to the water pump. When you walked around the truck, the noise was clearly coming from the bell housing area. When I got up on top of the engine on my hands and knees, I would have bet money that the noise was a loose flex plate bolt.

 

you cvan get a flashlight and a mirror and at the trans inspection port look and see if the flexplate cracked or maybe a bolt backed out. would be the easist to alleviate the flexplate bolts or crack plate

 

Thanks guys, ill try to get a video later today.
Skeet im going to give that a try and see if i can see anything.

 

i have a brand new flexplate in my garage im not gonna use,, pm me if u need it

 

Go ahead and pull your starter off and make sure the starter drive/bendix doesn't freely float around on the starter shaft. If it does that is bad and the bendix can rub up against the teeth on the flex plate and give you that nice ting ting ting ting broken flex plate sound. Had one doing this a while back. All that was broken was the starter drive return spring but when you can't buy parts to service this stuff it got a starter put on it but it was 8 years old and 150k anyway so it lived a good life.

 

Well guys the truck is at Coreys transmissions in san antonio. Charging me 100 bucks to change output shafts for 4wd and 125 to r&r trans.

 

did you ever figure out the noise? i had lose converter bolts which in turn helped break the flexplate and i was chasing that noise forever. well here it is....broken flexplate and ruined rear seal. well im not pulling it all back down to change the seal until its time for a new converter/tranny combo.

 

no not yet, the trans guy was finishing up some stuff on the trans thats going in before he pulls the other one out of the truck. My rear main seal is leaking pretty good too, it sounds like the same problem you had.