That's the one! 
Replacement Harmonic Balancer?
Le Mans Master
Joined: Oct 2012
Posts: 5,910
Likes: 49
From: CA
St. Jude Donor '17
Me too, especially as I'm planning a nice long trip. Coming up on 58,000 miles in my 06 vert and nary a sound upon startup or any other rpm. No squeak, wobble or concern...now, but...don't want to be stranded anywhere and have to pay for 'same as OEM' with predictable results. Damn ChevyInc. should be taking care of these as safety defects. There are enough failures that are documented aren't they? Hello GM!!!! You have a loyal but concerned owner base you know. And you do want to keep them don't you?
Drifting
Joined: Jan 2002
Posts: 1,498
Likes: 3
From: Sacramento CA
With this I have no question in my mind. ATI Super Dampener all the way. I had another aftermarket pulley on my C5, (ASP), and it physically destroyed my dual roller timing chain. I was lucky that I caught it before it broke completely.
Race Director
Joined: Oct 2005
Posts: 14,999
Likes: 200
From: Bay Area Ca.
Drifting
Joined: Oct 2004
Posts: 1,890
Likes: 7
From: Newcastle Oklahoma
It seams the last time I saw GM procedure sheet that it said 4.5 hours. But yes it is hard to change out things that are not broke or appear to be broke. I will change out the damper myself. I helped someone change one on my lift before, it will take me longer than 4.5 hours. . It would be much more difficult without a lift. You have to drop down the suspension and the rack. steering. Hind sight is always easy to say I wish I had of......
Race Director
Joined: Oct 2005
Posts: 14,999
Likes: 200
From: Bay Area Ca.
It seams the last time I saw GM procedure sheet that it said 4.5 hours. But yes it is hard to change out things that are not broke or appear to be broke. I will change out the damper myself. I helped someone change one on my lift before, it will take me longer than 4.5 hours. . It would be much more difficult without a lift. You have to drop down the suspension and the rack. steering. Hind sight is always easy to say I wish I had of......
Le Mans Master
Joined: Oct 2012
Posts: 5,785
Likes: 36
From: Tampa Florida
As like Wayne and Joe I have crossed my fingers prior to posting no problems with my 2008. That said, my LS2 GTO spit the pulley off and that was just barrels of fun, multiple new glazed belts and fluids in general just a-slingin' everywhere.
Drifting
Joined: Jan 2006
Posts: 1,819
Likes: 5
From: Annapolis Md.
Ati
;;My builder put mine on..It comes unassembled and he did NOT use blue loctite on the 9 bolts...Now I noticed some are coming out and some are broken off
My builder says he does NOT use loctite yet on the front damper it totally states, Must use blue loctite..Now with only 800 miles on my Cadillac 6.0 forged turboed CTSV I have to pull it out...It is a LOT easier than a C6...to get to...just some advice...USE THE BLUE LOCTITE....seeya 
My builder says he does NOT use loctite yet on the front damper it totally states, Must use blue loctite..Now with only 800 miles on my Cadillac 6.0 forged turboed CTSV I have to pull it out...It is a LOT easier than a C6...to get to...just some advice...USE THE BLUE LOCTITE....seeya
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Drifting
Joined: Apr 2010
Posts: 1,443
Likes: 7
From: Bristol raceway area
;;My builder put mine on..It comes unassembled and he did NOT use blue loctite on the 9 bolts...Now I noticed some are coming out and some are broken off My builder says he does NOT use loctite yet on the front damper it totally states, Must use blue loctite..Now with only 800 miles on my Cadillac 6.0 forged turboed CTSV I have to pull it out...It is a LOT easier than a C6...to get to...just some advice...USE THE BLUE LOCTITE....seeya
My builder says he does NOT use loctite yet on the front damper it totally states, Must use blue loctite..Now with only 800 miles on my Cadillac 6.0 forged turboed CTSV I have to pull it out...It is a LOT easier than a C6...to get to...just some advice...USE THE BLUE LOCTITE....seeya 
Unacceptable what happened to you. Another horror story.
The only person i trust is myself to work on my car.
Good luck
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
;;My builder put mine on..It comes unassembled and he did NOT use blue loctite on the 9 bolts...Now I noticed some are coming out and some are broken off My builder says he does NOT use loctite yet on the front damper it totally states, Must use blue loctite..Now with only 800 miles on my Cadillac 6.0 forged turboed CTSV I have to pull it out...It is a LOT easier than a C6...to get to...just some advice...USE THE BLUE LOCTITE....seeya
My builder says he does NOT use loctite yet on the front damper it totally states, Must use blue loctite..Now with only 800 miles on my Cadillac 6.0 forged turboed CTSV I have to pull it out...It is a LOT easier than a C6...to get to...just some advice...USE THE BLUE LOCTITE....seeya 
Safety Car
Joined: Apr 2007
Posts: 4,458
Likes: 325
From: Houston TX
Gearhead Jim,
You are not wrong in trying to arm yourself with the knowledge of a quality stock replacement damper. I had mine replaced Nov 28, 2011 @64k miles at Lonestar Chevy in Houston. This morning, I have terrible belt squeal and the damper is wobbling very slightly. Going to take it in and see what they say but the new damper comes with a 12 month, 12k mileage warranty. I'm only just outside that window so perhaps they will be reasonable.
You are not wrong in trying to arm yourself with the knowledge of a quality stock replacement damper. I had mine replaced Nov 28, 2011 @64k miles at Lonestar Chevy in Houston. This morning, I have terrible belt squeal and the damper is wobbling very slightly. Going to take it in and see what they say but the new damper comes with a 12 month, 12k mileage warranty. I'm only just outside that window so perhaps they will be reasonable.
Advanced
Joined: Oct 2010
Posts: 69
Likes: 0
From: Eugene Oregon
Lingenfelter quoted me $590 for the ATI Super Damper (Part# 917246), so I would not recommend them. Summit appears to have the best price that I can find around so I'll be ordering it from them (Almost $160 cheaper and free shipping).
For anybody else that's looking, the part numbers for the GM Balancer Bolt and Diamond Embedded Washer are:
12603843 - Diamond Embedded Washer
12557840 - Harmonic Balancer Bolt
Good luck!
For anybody else that's looking, the part numbers for the GM Balancer Bolt and Diamond Embedded Washer are:
12603843 - Diamond Embedded Washer
12557840 - Harmonic Balancer Bolt
Good luck!
Last edited by EgoTrippin; Feb 25, 2013 at 12:03 PM.
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
Lingenfelter quoted me $590 for the ATI Super Damper (Part# 917266), so I would not recommend them. Summit appears to have the best price that I can find around so I'll be ordering it from them (Almost $160 cheaper and free shipping).
For anybody else that's looking, the part numbers for the GM Balancer Bolt and Diamond Embedded Washer are:
12603843 - Diamond Embedded Washer
12557840 - Harmonic Balancer Bolt
Good luck!
For anybody else that's looking, the part numbers for the GM Balancer Bolt and Diamond Embedded Washer are:
12603843 - Diamond Embedded Washer
12557840 - Harmonic Balancer Bolt
Good luck!
Advanced
Joined: Oct 2010
Posts: 69
Likes: 0
From: Eugene Oregon
I paid $425. from Lingenfelter. if your doing installation yourself you may want to consider using ARP crank bolt. much easier to use and can be reused. 250 lb/ft and your done with it. GM crank bolt 37 lb/ft plus 140 degrees. the GM DEW washer does not fit any ATI hb I have installed and not necessary. call ATI's tech line. now would be the time to pin the crank for added insurance while you have it apart.
I'm not sure why Lingenfelter quoted so high, but the person I spoke to was pretty short with me and seemed like he was just interested in getting me off the phone. Maybe I would've had better luck if I would've emailed them. Oh well.
Burning Brakes
Joined: Nov 2012
Posts: 1,049
Likes: 1
From: Wisconsin
Should I proactively replace my Harmonic Balancer? I've a 2012 GS with 4K miles.
I mean, is it a given that the factory OEM balancer is likely to go bad eventually and I can avoid the hardship and risk of damage to the engine by replacing it with some of the replacement brands that you guys have mentioned in this thread?
Thanks in advance.
I mean, is it a given that the factory OEM balancer is likely to go bad eventually and I can avoid the hardship and risk of damage to the engine by replacing it with some of the replacement brands that you guys have mentioned in this thread?
Thanks in advance.
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
Should I proactively replace my Harmonic Balancer? I've a 2012 GS with 4K miles.
I mean, is it a given that the factory OEM balancer is likely to go bad eventually and I can avoid the hardship and risk of damage to the engine by replacing it with some of the replacement brands that you guys have mentioned in this thread?
Thanks in advance.
I mean, is it a given that the factory OEM balancer is likely to go bad eventually and I can avoid the hardship and risk of damage to the engine by replacing it with some of the replacement brands that you guys have mentioned in this thread?
Thanks in advance.
Thread Starter
Team Owner
Joined: Sep 2000
Posts: 25,009
Likes: 2,707
From: Far NW 'burbs of Chicago
St. Jude Donor '13
Should I proactively replace my Harmonic Balancer? I've a 2012 GS with 4K miles.
I mean, is it a given that the factory OEM balancer is likely to go bad eventually and I can avoid the hardship and risk of damage to the engine by replacing it with some of the replacement brands that you guys have mentioned in this thread?
Thanks in advance.
I mean, is it a given that the factory OEM balancer is likely to go bad eventually and I can avoid the hardship and risk of damage to the engine by replacing it with some of the replacement brands that you guys have mentioned in this thread?
Thanks in advance.
My procedure is to look at the HB every time I have the hood open with the engine running. That might be often enough, or not. Some people seem to experience rapid failure with no warning that they notice.
Fortunately, my GMPP goes well beyond the 5/100 powertrain warranty in months, which is what I need.
