Community Forums

747Driver · 03-18-2004, 08:20 PM

Well, like someone mentioned in another thread, you solve one noise problem and you then hear a dozen more.

I had a vibration in the front end that was bad from 65 to 72 MPH, so I avoided those speeds.

With new shocks and Equal in the front tires, no vibs, so into the 70 range I go. I notice a hum, and mild vibs from 68 to 71. It goes away when I come off the throttle. Back on the throttle and it's back if in the speed range of 68 to 71 MPH. It stays even if I down shift out of 5th gear, so I think it is rear of the tranny. It is definatly louder if under a load, like a slight incline.

Drive shaft, U joints? Is it normal, maybe a resonant range. Anyone else notice the same thing?

747Driver · 03-18-2004, 08:20 PM

Well, like someone mentioned in another thread, you solve one noise problem and you then hear a dozen more.

I had a vibration in the front end that was bad from 65 to 72 MPH, so I avoided those speeds.

With new shocks and Equal in the front tires, no vibs, so into the 70 range I go. I notice a hum, and mild vibs from 68 to 71. It goes away when I come off the throttle. Back on the throttle and it's back if in the speed range of 68 to 71 MPH. It stays even if I down shift out of 5th gear, so I think it is rear of the tranny. It is definatly louder if under a load, like a slight incline.

Drive shaft, U joints? Is it normal, maybe a resonant range. Anyone else notice the same thing?

clipperbob · 03-19-2004, 01:07 AM

I have not noticed this on ours, however it could be tire noise, or perhaps the rear diff. needs an adjustment?

DriVer · 03-19-2004, 09:05 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by 747Driver:
Is it normal, maybe a resonant range. Anyone else notice the same thing? <HR></BLOCKQUOTE>I would have a tendency to agree with your estimation of the situation about some kind of resonant harmonic. Just an out of the box question; How is the air pressures on all 6 tires, OK?

I don't have that much of a problem with noises.
<span class="ev_code_GREEN">If the little noises get too loud, I just turn up the Stereo</span>!

Pubtym · 02-11-2007, 03:05 PM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by 747Driver:
Well, like someone mentioned in another thread, you solve one noise problem and you then hear a dozen more.

I had a vibration in the front end that was bad from 65 to 72 MPH, so I avoided those speeds.

With new shocks and Equal in the front tires, no vibs, so into the 70 range I go. I notice a hum, and mild vibs from 68 to 71. It goes away when I come off the throttle. Back on the throttle and it's back if in the speed range of 68 to 71 MPH. It stays even if I down shift out of 5th gear, so I think it is rear of the tranny. It is definatly louder if under a load, like a slight incline.

Drive shaft, U joints? Is it normal, maybe a resonant range. Anyone else notice the same thing? </div></BLOCKQUOTE>

I have a 2006 Itasca with 12000 miles. In OD..at 62-65 mph..I hear a noticeable whine-howl with the tranny under load. When I back off on the load...it disappears.

I read in the Workhorse Owners Manual/Section 4/Service Information Quote:

"NOTICE: The rear axle of your vehicle has several large turning gears that can emit resonating noises which may be a normal operating characteristic, depending on vehicle load or vehicle speed."

max49 · 02-11-2007, 06:42 PM

If you get it while on the gas and don't hear it when you back off, it probably is in the differential. Om my F-150 I have that too and a mechanic told me he could shim the bearing, (whatever that means), but it would'nt hurt any thing if I could live with it the way it is.

Ultra RV Products · 02-11-2007, 06:58 PM

747,

Just for Duck's,try and shim the driveshaft angle down at the carrier bearing.Loosen the two bolts and install some washers above the mounting surface.Sometimes changing the angle will cancel that noise out

747Driver · 02-12-2007, 03:50 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brazels RV Performance:
747,

Just for Duck's,try and shim the driveshaft angle down at the carrier bearing.Loosen the two bolts and install some washers above the mounting surface.Sometimes changing the angle will cancel that noise out

</div></BLOCKQUOTE>

That sounds like an easy fix, I'll give it a try...thanks.

Pubtym · 02-12-2007, 08:48 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brazels RV Performance:
747,

Just for Duck's,try and shim the driveshaft angle down at the carrier bearing.Loosen the two bolts and install some washers above the mounting surface.Sometimes changing the angle will cancel that noise out

</div></BLOCKQUOTE>

Place a couple of thin fender type washers on/over the bolts so the mount surface/chassis frame piece holding the carrier bearing is slightly further away from the mounting bracket??? Is this correct?

Pubtym · 02-12-2007, 08:51 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by 747Driver:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brazels RV Performance:
747,

Just for Duck's,try and shim the driveshaft angle down at the carrier bearing.Loosen the two bolts and install some washers above the mounting surface.Sometimes changing the angle will cancel that noise out

</div></BLOCKQUOTE>

That sounds like an easy fix, I'll give it a try...thanks. </div></BLOCKQUOTE>

Let us know the results. Thanks

Full-Timers · 02-12-2007, 06:01 PM

This is something that should be done by a good driveline shop with the proper equipment to make the measurements. You can cause more problems than you cure without the proper measurements. It would be OK to do it as a test to see if the vibration goes away. If it doesn't, take the shims out. If it does, take the shims out and take it to a driveline shop to have it aligned properly.

Ultra RV Products · 02-12-2007, 06:09 PM

Well said FullTimers!

Pubtym · 02-13-2007, 02:54 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Full-Timers:
This is something that should be done by a good driveline shop with the proper equipment to make the measurements. You can cause more problems than you cure without the proper measurements. It would be OK to do it as a test to see if the vibration goes away. If it doesn't, take the shims out. If it does, take the shims out and take it to a driveline shop to have it aligned properly. </div></BLOCKQUOTE>

Agree. Found this info yesterday.
http://www.differentials.com/diagnose.html

I also have emailed WH tech support to see what they say on how they recommend I proceed.

Pubtym · 02-13-2007, 09:05 AM

After e-mail exchange yesterday with WH Tech Support, I visited local WH Service center in Sioux Falls. Interesting enough, manager recently worked a similar problem with another 2006 Itasca. He is completing forms for WH so as to begin trouble shoot. More to follow..