LT4 Lifter Noise
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Joined: Dec 2001
Posts: 51
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From: Groveland CA
LT4 Lifter Noise
Last week after my 150 mile weekly commute. I pulled into the garage and heard an awful clattering noise, at idle only. After much investigation I decided it was either too much octane booster hammering :smash: my pistons or lifters. :confused:
So I changed oil and used some prolong additive. Drove the commute on Monday and did not use octane booster, filled up with Chevron 92 as usual. That week it continued and was begining to sound like a singer sewing machine at idle. :( Deffinitely lifters. I was getting desperate, so I stopped into a Kragens and bought some Resoline additive. It claims to eliminate lifter noise.
It worked!!! :eek: Now I am worried, with 85K on this LT4
I checked My manuals and they say there is no adjustment for the 96 C4. :chevy GMs infinite wisdom.:mad
Can the LT4 roller rockers be adjusted? Should I go to 20/50 Mobile One? Do I need to replace lifters or cam? Anybody got any bright ideas? Thanks :)
So I changed oil and used some prolong additive. Drove the commute on Monday and did not use octane booster, filled up with Chevron 92 as usual. That week it continued and was begining to sound like a singer sewing machine at idle. :( Deffinitely lifters. I was getting desperate, so I stopped into a Kragens and bought some Resoline additive. It claims to eliminate lifter noise.
It worked!!! :eek: Now I am worried, with 85K on this LT4
I checked My manuals and they say there is no adjustment for the 96 C4. :chevy GMs infinite wisdom.:mad
Can the LT4 roller rockers be adjusted? Should I go to 20/50 Mobile One? Do I need to replace lifters or cam? Anybody got any bright ideas? Thanks :)
Le Mans Master
Joined: May 2000
Posts: 6,694
Likes: 1
From: Gurnee IL
Cruise-In II Veteran
Re: LT4 Lifter Noise (John Ruy)
Both my LT4 cars, one had 19k miles, one had 11k miles.
Both had noisy fuel injectors.
Both had noisy clutches (noticed it got quieter when I put the clutch in).
I just stopped worrying about every tapping noise under the hood.
:D
Both had noisy fuel injectors.
Both had noisy clutches (noticed it got quieter when I put the clutch in).
I just stopped worrying about every tapping noise under the hood.
:D
Thread Starter
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Joined: Dec 2001
Posts: 51
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From: Groveland CA
Re: LT4 Lifter Noise (Patrick96LT4)
I would agree. But this could be heard across the parking lot by those who don't know. :crazy: I'ts the Resoline that's got me wondering. :confused:
Thread Starter
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Joined: Dec 2001
Posts: 51
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From: Groveland CA
Re: LT4 Lifter Noise (vettedave)
You may have worn cam lobes. At 85 K it isn't inconceivable.
Check for loose pushrods with the valves closed.
:smash:
Check for loose pushrods with the valves closed.
:smash:
Are we talking replacement?
Le Mans Master
Joined: Aug 1999
Posts: 7,339
Likes: 137
From: WilkesBarre PA
Re: LT4 Lifter Noise (John Ruy)
The LT4 rockers are non adjustable. Pull the covers and re-torque the nuts, and check for any with too much play. If a nut loosened up it will make the loud noises. Also if there is alot of play in one you may have a lifter going bad.
Le Mans Master
Joined: Oct 2000
Posts: 6,362
Likes: 30
From: Oak Harbor WA
Re: LT4 Lifter Noise (RichS)
Yeah, you might have pulled a rocker nut loose or worn something else out beyond limits. That thick honey stuff you use only masks the problem for a little while. Get a mechanics stethoscope and you might be able to narrow it down to one side or the other to save some work and time. You can touch it to the top of the rocker arm studs to hear which one is the loudest when the valve cover is removed. Good luck... :seeya
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Le Mans Master
Joined: Jan 2000
Posts: 6,595
Likes: 1
From: Thornton CO
Re: LT4 Lifter Noise (John Ruy)
If after everything you still can't find the "Tapping" noise, pull the oil pan and check those rod bearings - I just went through a similar scenario and it wound up being bearings :eek:
