Typical timeframe to replace harmonic balancer
Thread Starter
Melting Slicks
Joined: Jan 2007
Posts: 3,021
Likes: 133
From: Conejo Valley CA
Typical timeframe to replace harmonic balancer
Hey Guys,
I was wondering, as part of a preventative maintenance, after how many miles would you guys replace the harmonic balancer? My 2002 recently passed 100k miles. Just wondering if I need to consider this? My understanding is if there is a problem with it, it can lead to bigger problems.
Thanks!
I was wondering, as part of a preventative maintenance, after how many miles would you guys replace the harmonic balancer? My 2002 recently passed 100k miles. Just wondering if I need to consider this? My understanding is if there is a problem with it, it can lead to bigger problems.
Thanks!
Melting Slicks
Joined: Oct 2007
Posts: 2,375
Likes: 426
I don't think it's got much to do with miles or years. It's when the rubber inside the balancer lets go it's time. I have a 1998 with 150K miles and it went two years ago in December.
It was fine right up til it walked backwards and ran into the engine.
I had just put new belts, hoses, pulleys and tensioners, water pump and radiator in late September - October.
It was fine in September but by December it was toast and had to be replaced between Christmas and New Years.
Did the front seal at the same time. Had a devil of a time getting the steering rack purged of air bubbles.
I would say that at 100K miles on a 2002 you should think about it.
Like in sailing, people ask "when should I shorten sail?". You should shorten sail when the thought occurs to you.
It was fine right up til it walked backwards and ran into the engine.
I had just put new belts, hoses, pulleys and tensioners, water pump and radiator in late September - October.
It was fine in September but by December it was toast and had to be replaced between Christmas and New Years.
Did the front seal at the same time. Had a devil of a time getting the steering rack purged of air bubbles.
I would say that at 100K miles on a 2002 you should think about it.
Like in sailing, people ask "when should I shorten sail?". You should shorten sail when the thought occurs to you.
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
Two types of HB problems, one is the prior mentioned separation and the other is the HB walking or moving forward. The prior is often from high mileage (100,000-200,000 mile) and the other from high rpms for extended periods of time (W2W,autocross, HPDE,drags, etc). They both require replacement, aftermarket is better choice and pinning the crank is recommended. When mine went, 30K, it was problem #2
Drifting
Joined: Jan 2008
Posts: 1,722
Likes: 138
From: Florida
St. Jude Donor '09
Hey Guys,
I was wondering, as part of a preventative maintenance, after how many miles would you guys replace the harmonic balancer? My 2002 recently passed 100k miles. Just wondering if I need to consider this? My understanding is if there is a problem with it, it can lead to bigger problems.
Thanks!
I was wondering, as part of a preventative maintenance, after how many miles would you guys replace the harmonic balancer? My 2002 recently passed 100k miles. Just wondering if I need to consider this? My understanding is if there is a problem with it, it can lead to bigger problems.
Thanks!
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Le Mans Master
Joined: Feb 2021
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From: Florida
2025 Corvette of the Year Finalist - Unmodified
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Most don’t realize it’s actually cam related!
If you wish to install a better cam, swap out the HB “while you’re in there..”
If your HB is showing signs of failure, swap out the cam “while you’re in there…”
If you wish to install a better cam, swap out the HB “while you’re in there..”
If your HB is showing signs of failure, swap out the cam “while you’re in there…”
Pro
Joined: Dec 2021
Posts: 547
Likes: 230
I finally thought it through and came up with a theory why these balancers seem to be a problem. In the past, up through the C4 at least the L98s, (I'm not intimately familiar with the LT1), the front pulley was always a separate part that bolted to the center part of the HB. Thus the outer ring of the HB only had to dampen the engine harmonics and that's it. Now, the outer ring of the HB has become the pulley, so it is subjected to not only the engine harmonics but also the torque and the harmonics of the whole accessory drive system. To me, no wonder they fail.
Melting Slicks
Joined: Apr 2019
Posts: 2,466
Likes: 700
From: Clark, NJ
I finally thought it through and came up with a theory why these balancers seem to be a problem. In the past, up through the C4 at least the L98s, (I'm not intimately familiar with the LT1), the front pulley was always a separate part that bolted to the center part of the HB. Thus the outer ring of the HB only had to dampen the engine harmonics and that's it. Now, the outer ring of the HB has become the pulley, so it is subjected to not only the engine harmonics but also the torque and the harmonics of the whole accessory drive system. To me, no wonder they fail.
Melting Slicks
Joined: Apr 2021
Posts: 2,191
Likes: 82
The camaro ls1 f bodies hold up real well i think but i did switch to a pb on my 98 z28 25% ud in 2011 around 130-140k miles.
Its about a 5hr job if auto you need to remove the starter and purchase one of those cheap flywheel locking tools for 12-15$ on amazon or ebay. Thats what i got worked great. Oreillys is the only place that has a 250ftlbs torque wrench to rent a tool get all your money back once returned 235 ftlbs with arp bolt.
I did mine with cam swap as the rubber was bad shape didnt walk off but didnt want to end up roadside stranded.
Remove the tie rod ends both rack bolts and ebcm bracket. and slide the rack out the passenger side not all the way partially and angled up to have access to the balancer. bolt. Use the flexplate flywheel locking tool and i used electric 1/2" impact removed bolt also autozones loan a tool balancer puller. Torqued new balancer with arp bolt to 235 ft lbs.
Its about a 5hr job if auto you need to remove the starter and purchase one of those cheap flywheel locking tools for 12-15$ on amazon or ebay. Thats what i got worked great. Oreillys is the only place that has a 250ftlbs torque wrench to rent a tool get all your money back once returned 235 ftlbs with arp bolt.
I did mine with cam swap as the rubber was bad shape didnt walk off but didnt want to end up roadside stranded.
Remove the tie rod ends both rack bolts and ebcm bracket. and slide the rack out the passenger side not all the way partially and angled up to have access to the balancer. bolt. Use the flexplate flywheel locking tool and i used electric 1/2" impact removed bolt also autozones loan a tool balancer puller. Torqued new balancer with arp bolt to 235 ft lbs.
Racer
Joined: Oct 2021
Posts: 389
Likes: 76
From: Chicago
Hey Guys,
I was wondering, as part of a preventative maintenance, after how many miles would you guys replace the harmonic balancer? My 2002 recently passed 100k miles. Just wondering if I need to consider this? My understanding is if there is a problem with it, it can lead to bigger problems.
Thanks!
I was wondering, as part of a preventative maintenance, after how many miles would you guys replace the harmonic balancer? My 2002 recently passed 100k miles. Just wondering if I need to consider this? My understanding is if there is a problem with it, it can lead to bigger problems.
Thanks!
Racer
Joined: Mar 2018
Posts: 456
Likes: 144
From: Frederick Colorado
"Cam-related," this is what you tell your wife to justify the expenditure of an additional $2,200 in parts and tuning expenses, right?
.
Joined: Apr 2013
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From: Oregon
St. Jude Donor '14-'15-'16-'17-'18-'19-'20-'21-'22-'23
Melting Slicks
Joined: May 2013
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From: New Jersey
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St. Jude Donor '25
I had mine replaced at the Chevy Dealer this past April with 92k miles as a precaution.