Used Class C -- Rattle upon deceleration

[atarsha]

Hello All!

My wife and I recently bought a used 2003 Fleetwood Tioga SL 31 foot Class C. On our current trip, we noticed a noise, I can best describe as a rattle/very slight grinding noise only when decelerating at around 55-65 MPH. No noise is heard while accelerating or maintaining speed.

I first thought it was a loose exhaust heat shield, so I checked those very thoroughly. I then greased the U-joints, and although there is no zerk on the driveshaft support bearings, I packed grease around them the best that I could, but doubt I really got any inside them.

From the drivers seat it sounds like it's directly over my right shoulder on the floor, but my wife believes it's further back near the rear axle.

I know diagnosing noises based on online descriptions is difficult, but I'm not having much luck myself here. Any suggestions? We are away from home by thousands of miles, so I'd love to track this down before having to make the trek back.

Thanks for any suggestions you may have.
-Alex

[atarsha]

atarsha wrote:

bsinmich wrote:
I am curious about your driving position when the noise is over your R. shoulder on the floor. Have you checked for stones in a wheel cap?

I don't think it's that simple, but yes I have checked.

It seems to be behind me but below the floor in the middle of the rig, like the dirveshaft.

Mine sounds like two different noises, a rattling, and a grinding or deep howl. I find it strange that it started halfway through the trip, and is only noticed at certain speed (higher speeds) It is NOT related to RPM, but speed.

Interestingly I just remembered that I hear it while decelerating around that speed and VERY briefly when re-apply accelerator afterwards.

It's like it only happens when coasting at higher speed, and when first re-applying power.

[atarsha]

bsinmich wrote:
I am curious about your driving position when the noise is over your R. shoulder on the floor. Have you checked for stones in a wheel cap?

I don't think it's that simple, but yes I have checked.

It seems to be behind me but below the floor in the middle of the rig, like the dirveshaft.

[pnichols]

I may have the same rattle that started after owning the motorhome for around 3 years.

We have a rattling noise like two pieces of tin vibrating against each other. It happens at certain speeds - in the range of 35 MPH to 45 MPH in top gear. In lower gears the rattling can occur at lower speeds.

Our noise sounds like it's coming from under the front floor near the motor or somewhere up around the motor itself. Mechanics have checked everything under the front area, such as the exhaust manifolds and heat shields ... except for removing the doghouse and looking around the motor.

I think it's some tin or sheet metal pieces up around the motor. I'll find it and fix it one of these days when I get off my duff and remove the doghouse. I'm guessing it'll be something obvious and simple to eliminate around the motor - where mechanics have not yet checked.

[bsinmich]

I am curious about your driving position when the noise is over your R. shoulder on the floor. Have you checked for stones in a wheel cap?