Mystery vibration
Instructor
Joined: Nov 2018
Posts: 122
Likes: 61
From: Cato, WI
I had a similar "Harmonic" vibration at 55 plus for years. Went through pretty much same iterations of throwing new wheels, tires and parts at it. Last thought was to go old school and bought a HF bubble balancer. Checked and all four were off a (small?) amount. Stripped all the weights and rebalanced on the bubble. Major improvement. Guess you can't get it perfect this way. But gravity is your friend.
Last edited by tcfamy; Feb 20, 2024 at 12:21 PM. Reason: spelling
Pro
Joined: Aug 2010
Posts: 622
Likes: 169
From: Montgomery Texas
This reminds me of an amusing anecdote (I can laugh now, but it wasn't funny at the time!). We had a harmonic issue at around about 63 mph. The amplitude varied from car to car, but most cars exhibited the issue. We went though a couple of cars and ended up empty handed. We then entered "grasping at straws" mode and eventually got around to pulling the belts off of the front of the engine, which fixed the car!!! Well, to be honest, it didn't actually fix the car, but it did eliminate the vibration. To make a long story short, an asymmetrical belt was needed to break up the harmonic vibration and one of the accessory mounts needed to be strengthened in order to keep it from resonating in this problematic frequency range.
I'm not making a Corvette diagnosis, mind, I'm just underscoring how obscure and difficult some of these NVH issues can be to diag and resolve. Some driveline vibrations have nothing to do with what we would normally consider to be the driveline.
I'm not making a Corvette diagnosis, mind, I'm just underscoring how obscure and difficult some of these NVH issues can be to diag and resolve. Some driveline vibrations have nothing to do with what we would normally consider to be the driveline.
