Vibration @ 60mph

[SWithrow]

It has been awhile since I have posted something but I have a vibration that I have been chasing for months. I replaced the front hubs (right side had play), and while replacing the hubs I replaced the front axle joints (245k onthe joints). The front and rear drive shafts have new joints and a new tail shaft housing, I also replace the rear inner and outer bearings (both sides had a little play and they too had 245k on them. While driving and reach 60 mph I have a slight vibration almost as if I drove over rumble strips then dissipates once I reach 70mph. Ball joints and tie rods are tight, new shocks and tires. Oh, and I have driveshaft balancers installed. Any ideas or suggestions would be appreciated.

 

[cerberusiam]

Check the brake rotors for runout. Once they get beyond a bare minimum they can introduce vibrations.

The other source is usually the rear DS, especially if it is speed sensitive.

 

[NAllen]

Check tires and wheels?

 

[SWithrow]

I towed the horses this past weekend and one of the things I do is inflate the air bags to 65 psi (norm is 20). I had to run into town today and forgot to deflate the bags and the truck ran great. Could this be the out put bearing on the transfer case? I'm going to place my go pro under the truck and see what's going on (I hope)





The tires and rims are good.

 

[cerberusiam]

Do you have a 1 piece or 2 piece rear DS?

 

[SWithrow]

One, I also have video that I will try to up load if possible.

 

[SWithrow]

Is this normal?
https://www.youtube.com/watch?v=xfUc04ixjoQ#action=share

 

[crabman]

If you have a smart phone, there is a app for diagnosis of driveline related vibrations.
https://www.youtube.com/watch?v=GuI0hH2TuxQ

 

[Prairie Dog]

That NVH app is freaking amazing.

 

[seafish]

In your video, there is a harmonic dampner (the ring mounted on the transfer case tail shaft) that is known to eventually fail and cause vibrations.

NOT saying that this is definitely the source of the vibration, but it is a definite possibility and should be investigated.

Replacements may no longer be available, but you can check here--


http://www.quad4x4.com/catalog/qu50752

IIRC, some people have had success by removing the ring and having the driveshaft rebalanced.

Here is a single post about it--

https://www.turbodieselregister.com...nd-a-possible-real-cure?p=2284054#post2284054

 

[crabman]

Without a doubt! They covered ALL the bases for any time of vibration with it too. Looks as if the informational setup would take some time but the results are worth the initial time & effort.

 

[seafish]

And here is another post talking about removing the DS dampener and rebalancing the shaft led to substantial vibration reduction--

http://www.cumminsforum.com/forum/3...arend-vibration-killing-me-6.html#post9366617

 

[SWithrow]

thanks for the replies!

 

[Prairie Dog]

Just checked, that NVH app is $400!
Fail.

 

[cerberusiam]

Still need to check run out on the brake rotors, both on the vehicle and a machine if warranted. Warping of the rotors and alignment on the hubs is a known issue with the composite rotors.

The t-case moving around is normal, if it doesn't move pieces ply off the drive train when the TQ rise hits. That isn't anything abnormal as long as you don't have excess play in the t-case slip joint.

At this point the damper on the rear shaft is probably doing more harm than good. It is a bandaid to attempt to stop the harmonics in the steel DS's, once the rubber wears out it introduces more problems than it fixes. Between the steel DS and the crappy flange on the rear diff it is hard telling where the issue is. If you want to fix it permanently and correctly, a custom 5" aluminum DS and ditching the rear flange is the preferred way. You can balance and mess around forever with a steel DS and it will never cure the problem, just mask it for a while then it comes back.