2 piece drive shaft to 1

[Andy4639]

Ok just crawled under it and put several wraps around the center of the shaft. I tapped the housing with my finger and it sounds like a tuning folk. It rings like it's hollow! Is there anyway to put insulation in it other than cutting it open and inserting it. I figure not but thought I would ask.

I guess I need to call them and see what they would charge me to fill it.Can I drill a hole in it and put that wall foam stuff in it?

[Keith Seymore]

Originally Posted by Andy4639

[B][COLOR="Red"]Ok just crawled under it and put several wraps around the center of the shaft. I tapped the housing with my finger and it sounds like a tuning folk. It rings like it's hollow! Is there anyway to put insulation in it other than cutting it open and inserting it. I figure not but thought I would ask.

Slow down, there, pahdnuh...drive it first. Just because it rings when you hit it with your finger doesn't mean it is a problem.

For any noise issue you have to have three things: an input (aka "the hammer"), a responder ("the bell") and a noise transmission path (either airborne or structure borne). Take away any one of those elements and you no longer have a noise issue.

So - if nothing is hammering on the shaft - then it will not respond and there is no ringing. I'd drive it and see if it's an issue before going too far down the path of filling it with foam.

SIDEBAR:

Just for fun - More science: if it is rear axle mesh frequency that you are hearing (aka "axle whine") then filling the shaft will not help. Axle whine is manifested by exciting the shaft torsionally (ie, it is oscillating like a rubber band, back and forth, while rotating at speed) so you need to kill the shaft by adding a torsional damper.

Using the above "bell" analogy:

Input: "non conjugate" meshing action between the rear axle ring gear and pinion gear

Responder: the drive shaft responds torsionally in accordance with the number of teeth on the pinion gear. Said differently, for a 3.73 rear axle (41 teeth divided by 11 teeth) you can measure a frequency spike coincident with 11th order of propshaft rotation (11 "kicks" per rotation of the shaft). You can kill this response in two ways:
a) Fix the axle mesh
b) Add a torsional damper (like a harmonic balancer) to the shaft. Typically the front u joint is a more suitable location since the shaft amplitude is larger farther away from the input. You may have noticed some of these on C/K trucks as well as M/L vans (because I put them there).

Transmission path: typically is structurally. You can make the noise go away in a Suburban or Van by disconnecting the rear suspension from the body/frame. That may not be a viable option in real life.

K

[Keith Seymore]

...

[ERASER5]

Well, Andy, I was going to volunteer to listen to your noise (read take ride in your sweet truck), but it seems you are leaving for to the beach just as I get to Greenville this weekend. My loss. Hope you find your noise.

[brad_man_72]

^science!

They shouldn't charge you anything to stuff the shaft. If you tap on a shaft it will ring a little even if it is stuffed. Take it for a drive before you jump to too many conclusions.

D*&n you kieth! You know how many times those big a#% dampners smashed my fingers!

Some factory shafts have a short inner steel tube isolated by rubber as a dampner/suffing... those won't smash your fingers KIETH!

[Andy4639]

Man you all need to ease up. All I did was ask a question about filling the the thing up. It wasn't like I meant I was going to do it right then. I was just noting what i found.
I just drove the truck 289 miles to Myrtle beach. The tape made it a lot better but it's still there but not near as loud as it was before. At 60-70 it barely noticeable but over 75 and it starts being a pain again.

[Andy4639]

Originally Posted by ERASER5

Well, Andy, I was going to volunteer to listen to your noise (read take ride in your sweet truck), but it seems you are leaving for to the beach just as I get to Greenville this weekend. My loss. Hope you find your noise.

Sorry.

[Motoxrrar]

Did you wrap the tape at the trans end or the diff end? I would go to Home Depot and buy some tar tape ( sound deadening tape ) wrap just one turn and then Some duct tape to hold it in place at the trans end. It would help a lot better.

[brad_man_72]

If the tape changed it, the shaft needs to at least be checked by the builder. They should fix it for free.

Id call and bait them by asking what they use to stuff their shafts, when the say they don't stuff the shafts you can tell them that you know why your shaft is ringing.

Sorry, we didn't meant to get all worked up. Some people are crazy enough to try "great stuff" in their shaft, ruining the ballance and voiding any type of warranty your driveshaft might have.

[Andy4639]

Originally Posted by brad_man_72

If the tape changed it, the shaft needs to at least be checked by the builder. They should fix it for free.

Id call and bait them by asking what they use to stuff their shafts, when the say they don't stuff the shafts you can tell them that you know why your shaft is ringing.

Sorry, we didn't meant to get all worked up. Some people are crazy enough to try "great stuff" in their shaft, ruining the ballance and voiding any type of warranty your driveshaft might have.

Ok so your saying the shaft needs to be checked for... balancing are having the isulation installed are both.
This drive shaft is under warrinty so no I'm not going to do anything until I talk with them.
Well I headed out to the car show so it will be late this afternoon before I'm back.
A little video of the ride down.

http://www.youtube.com/watch?v=2MZpBt70JVc

[Keith Seymore]

Originally Posted by brad_man_72

^science!

They shouldn't charge you anything to stuff the shaft. If you tap on a shaft it will ring a little even if it is stuffed. Take it for a drive before you jump to too many conclusions.

D*&n you kieth! You know how many times those big a#% dampners smashed my fingers!

Some factory shafts have a short inner steel tube isolated by rubber as a dampner/suffing... those won't smash your fingers KIETH!

LOL - SCIENCE!!

I think some of the shafts had a cardboard liner as well.

There's a lot going on there, for it just being a piece 'a pipe with some yokes on the end, eh?



K

[brad_man_72]

Originally Posted by Andy4639

Ok so your saying the shaft needs to be checked for... balancing are having the isulation installed are both.
This drive shaft is under warrinty so no I'm not going to do anything until I talk with them.
Well I headed out to the car show so it will be late this afternoon before I'm back.
A little video of the ride down.

http://www.youtube.com/watch?v=2MZpBt70JVc

The shafts ballance is probably fine (right now). They will have to cut the weld yoke out to check for stuffing, that will affect the ballance so will adding stuffing, so the shaft will need to be reballanced even if that currently isn't an issue.

[Andy4639]

Ok thanks I know what I have to do now. When I get back to town I need to call them and setup a time to carry it over. Thanks.