Pontiac G8 Forum banner
1 - 16 of 16 Posts

·
Registered
Joined
·
351 Posts
Discussion Starter · #1 ·
My car started making a strange noise, kind of a squeeky tick, last week, all of the sudden. It has been consistent, same volume, and is definitely correlated with rpm. Car has been cammed for 70k miles, much highway, adult driven. RCR cam, LS7 lifters, BTR pushrods, trunions.... I pulled the valve covers today and everything looked okay, did not pull the rockers..... Also used a mechanic stethoscope. Definitely not the injectors, but otherwise inconclusive. Pretty sure it's coming from the driver's side. Thoughts? I don't think it's a collapsed lifter, but beyond that....? Could it be a bent pushrod rubbing? Worse would be a lifter failure, but how do those sound? Thanks.
 

·
Registered
Joined
·
4,909 Posts
When you did the cam and lifters. We’re the lifter trays new too?
 

·
Registered
Joined
·
351 Posts
Discussion Starter · #4 ·

·
Registered
Joined
·
92 Posts
As a person with a lifter issue right now, the sound you describe is exactly what I am hearing.
 

·
Registered
Joined
·
351 Posts
Discussion Starter · #6 ·
As a person with a lifter issue right now, the sound you describe is exactly what I am hearing.
What exactly is your lifter issue? Is it collapsed or is something wrong with the roller? I’m not too familiar with non dod lifters failing. I have ls7 ones.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
4,909 Posts
Any GM lifter can fail. The non-DOD as just less often. 70k is early, but not unheard of.
We’re they loose lifters of in all GM packaging? Could be fakes?
 

·
Registered
Joined
·
351 Posts
Discussion Starter · #8 ·
Any GM lifter can fail. The non-DOD as just less often. 70k is early, but not unheard of.
We’re they loose lifters of in all GM packaging? Could be fakes?
I don’t recall. Dod delete kit bought from Pace performance like 8 years ago. How do they fail? Any way to conform without removal of heads?


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
4,909 Posts
How do they fail? It could be the cam you are running. They are just stock lifters. Once you run cams .600” and above it pushes them to the limit. It could also be a oil pressure problem. In 8 years the O ring on the pump inlet could be leaking. What’s your oil pressure at hot idle?
 

·
Registered
Joined
·
92 Posts
What exactly is your lifter issue? Is it collapsed or is something wrong with the roller? I’m not too familiar with non dod lifters failing. I have ls7 ones.


Sent from my iPhone using Tapatalk
Diagnosis was damaged lifter and cam. Not saying that is what you have, just that the sound you describe is similar to what I hear. Almost sounds like a small bird chirp or the squeak of a belt...definitely changes as RPM's change too.
 

·
Registered
Joined
·
351 Posts
Discussion Starter · #11 ·
How do they fail? It could be the cam you are running. They are just stock lifters. Once you run cams .600” and above it pushes them to the limit. It could also be a oil pressure problem. In 8 years the O ring on the pump inlet could be leaking. What’s your oil pressure at hot idle?
25 psi hot idle in park.

I was asking what form the failure takes? Collapsed so I have play in the pushrod to rocker? Or is it the roller chewing up my cam? Any way I can determine without pulling the heads?


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
180 Posts
25 psi hot idle in park.

I was asking what form the failure takes? Collapsed so I have play in the pushrod to rocker? Or is it the roller chewing up my cam? Any way I can determine without pulling the heads?


Sent from my iPhone using Tapatalk
I had the same chirping sound last year on mine. Turned out to be collapsed DOD lifter. The lifter was contacting the camshaft. Chewed up lifter and marked camshaft. Lifter might be rotated in lifter tray also. Here's a picture of lifter and camshaft
Automotive tire Office supplies Bicycle part Writing implement Office equipment
Hand Finger Wood Nail Thumb
 

·
Registered
Joined
·
4,909 Posts
It can be either. Although low oil pressure is known to take out DOD lifters. At high lifts, not enough pressure can allow a lifter to bottom out. #2 cam bearing wear is also a source. A lifter rotating in the tray is the tray wearing out. Lifter trays can start wearing out with stock cams around 100+k. The higher the lift I would expect the trays to wear faster. I would say pull the heads is the minimum. See the lifters and cam lobes.
Then you can determine if just the oil pan needs to be cleaned or the engine pulled
 

·
Registered
Joined
·
351 Posts
Discussion Starter · #14 ·
I gotta say I'm disappointed, I hadn't heard about LS motor lifter trays wearing out. Considering selling the car, I no longer have the space, desire, or extra vehicle to deal with this. Honestly my plan was to keep the car another year or so and then move on....
 

·
Premium Member
Joined
·
63 Posts
How about the service book saying 100,000 miles change plugs Leeds coils change oil & filter replace lifters & trays. it only takes 6 hours if all else is ok & around au$1,000.00 or would we take the risk and wait for the squeak?
 

·
Registered
Joined
·
4,909 Posts
What ever the exact cause is. A lifter/ cam problem only get worse if you drive it.
Ace does list Endurance/DOD cams. Gives you the duration but with a .558 lift you don’t beat the life out of the valve train.
 
1 - 16 of 16 Posts
Top