Community Forums

tigersharkjd · 04-12-2013, 04:09 PM

I have noticed a sound in our 2013 Winnebago Tour like the bottom of a metal drum popping out when we back up, go over uneven ground or begin to move forward after parking. It seems to come from the rear of the coach. It is not a constant, it just makes that sound once, maybe twice. I heard this on another 2013 Winnebago Tour last week at another campground when it was pulling out and wanted to see if it is heard by other Maxum owners. We have a Maxum chassis with a tag axle. Thanks for any thoughts.

redfire312 · 04-12-2013, 04:21 PM

I would think the sound would be coming from the universal joints on your driveshaft

TeJay · 04-12-2013, 04:39 PM

What he said is a possibility. That's an easy one to check. Crawl under and do a visual inspection around the U-joint. If you see and brown dust it would indicate worn U-joint. If you see nothing then just push up and down on the drive shaft while watching the U-joint. Any movement indicates a worn joint. Now put it in neutral and twist the drive shaft back and forth. Again any movement and it's worn.
Here's one more item that could cause it. I worked and taught automotive for 35 years and never encountered this until last month. We have an F-150 and I started noticing a clunking sound when taking off and stopping. It's not the same sound you get when you put it in gear. It made it when accelerating or when stopping. I stopped into the Ford garage and talked to the service manager. Here's what it was.

When you accelerate or slow down the differential will twist up and down. When that happens the drive shaft will telescope inside the tail shaft of the transmission. It gets longer then shorter to allow movement of the differential. The grease in the spline shaft of the drive shaft has dried out and needs to be replenished. It's an expensive grease and there is a TSB (Technical service bulletin) on that issue.

Neither problem is very costly to fix. There may be some other issues that could cause the clunk but check these first.

Almost forgot. Check all U-joints not just the one out of the tranny.

TeJay

tigersharkjd · 04-18-2013, 05:56 PM

Quote:

Originally Posted by TeJay

What he said is a possibility. That's an easy one to check. Crawl under and do a visual inspection around the U-joint. If you see and brown dust it would indicate worn U-joint. If you see nothing then just push up and down on the drive shaft while watching the U-joint. Any movement indicates a worn joint. Now put it in neutral and twist the drive shaft back and forth. Again any movement and it's worn.
Here's one more item that could cause it. I worked and taught automotive for 35 years and never encountered this until last month. We have an F-150 and I started noticing a clunking sound when taking off and stopping. It's not the same sound you get when you put it in gear. It made it when accelerating or when stopping. I stopped into the Ford garage and talked to the service manager. Here's what it was.

When you accelerate or slow down the differential will twist up and down. When that happens the drive shaft will telescope inside the tail shaft of the transmission. It gets longer then shorter to allow movement of the differential. The grease in the spline shaft of the drive shaft has dried out and needs to be replenished. It's an expensive grease and there is a TSB (Technical service bulletin) on that issue.

Neither problem is very costly to fix. There may be some other issues that could cause the clunk but check these first.

Almost forgot. Check all U-joints not just the one out of the tranny.

TeJay

We are at the Winnebago factory and the "clunk" noise is caused by a metal panel that is flexing and is being fixed.

TeJay · 04-18-2013, 11:10 PM

Great, That was an easy fix. Did you drive there just for that or were you in the area anyway??? I think we are going there in the next few weeks to see how they are made and to get a better look at the floor plans .

TeJay

tigersharkjd · 04-19-2013, 04:38 AM

Quote:

Originally Posted by TeJay

Great, That was an easy fix. Did you drive there just for that or were you in the area anyway??? I think we are going there in the next few weeks to see how they are made and to get a better look at the floor plans .

TeJay

We had a typical list of items on a new coach, along with some stainless steel trim and paint issues. It is cold, has been raining and last night it snowed.

FIRE UP · 04-27-2013, 09:46 AM

Well Gang,
I just finished my "Could this be an MMDC problem" issue and it wasn't the MMDC, if any of you read the thread. Anyway, we also have a major "clunk" as the brakes are applied, especially in very low/slow speeds. I have a hard time thinking it's the "S" cams in the front brakes but, I have no problem removing the wheels and tires to do an in depth inspection to see what I can see. It sure sounds and feels like a worn spring (uni-leaf) bushing or something similar to it. I would think that if the "S" cams were acting up, then the brakes would have "jolting" effects and not be smooth upon application. But, that's only my theory. We'll see, when I get them torn down later today.
Scott

tigersharkjd · 04-27-2013, 10:24 AM

Winnebago factory discovered the "clunk bottom of 50 gal barrel sound" was in fact a piece of metal panel behind the engine compartment in the center of the frame that was flexing. They cut a section out of it that seems to have provided enough relief to stop the noise. I want to look and see what the panel may have been protecting toward the front of the coach.

Pusherman · 04-27-2013, 02:38 PM

Quote:

Originally Posted by FIRE UP

Well Gang,
I just finished my "Could this be an MMDC problem" issue and it wasn't the MMDC, if any of you read the thread. Anyway, we also have a major "clunk" as the brakes are applied, especially in very low/slow speeds. I have a hard time thinking it's the "S" cams in the front brakes but, I have no problem removing the wheels and tires to do an in depth inspection to see what I can see. It sure sounds and feels like a worn spring (uni-leaf) bushing or something similar to it. I would think that if the "S" cams were acting up, then the brakes would have "jolting" effects and not be smooth upon application. But, that's only my theory. We'll see, when I get them torn down later today.
Scott

Scott, I bet ya a nickel it is the S-cams in the front brakes binding up.

FIRE UP · 04-27-2013, 05:07 PM

Quote:

Originally Posted by Pusherman

Scott, I bet ya a nickel it is the S-cams in the front brakes binding up.

Mr Pusherman,
I see that nickel and raise you, 10 cents. I will "call" when I get the front wheels off either later today or, tomorrow, stay tuned.
Scott

Dunner · 04-27-2013, 05:44 PM

Seems to me a simple cross or vertical cut would have been sufficient. You may now be getting heat where you don't want it.

FIRE UP · 04-27-2013, 06:27 PM

Quote:

Originally Posted by Dunner

Seems to me a simple cross or vertical cut would have been sufficient. You may now be getting heat where you don't want it.

Huh?? I'm not exactly sure what you mean here Mr Dunner. I now have the right front wheel off and the drum. I've taken pictures of the S cam and I've also removed the roller for the bottom shoe. Nothing seems to be out of the ordinary. While the portion of the S cam is not a finely polished surface, nor is the surface of roller, they are both "round" and have no obvious problems that I can see. I will do further inspections to see if any thing else looks odd. Unless I find something that looks "galled" or, extra-ordinarily rough, I'll dab a bit of grease on the contact points and slap it all back together.
Scott

Dunner · 04-27-2013, 06:40 PM

Quote:

Originally Posted by tigersharkjd

Winnebago factory discovered the "clunk bottom of 50 gal barrel sound" was in fact a piece of metal panel behind the engine compartment in the center of the frame that was flexing. They cut a section out of it that seems to have provided enough relief to stop the noise. I want to look and see what the panel may have been protecting toward the front of the coach.

Talking to the OP.

FIRE UP · 04-28-2013, 12:35 PM

Quote:

Originally Posted by Pusherman

Scott, I bet ya a nickel it is the S-cams in the front brakes binding up.

Well Don,
You won. I owe you 15 cents. I pulled both front wheels and drums. The brakes (and rig) have almost 50K on them. They are still round 5/8" - 11/16" thick. Enough to go another 40K +. But, the S cams were just a tad pitted, not all that bad. I backed off the brake adjustment and removed both rollers from both sides of the coach. I cleaned them off, (not that you could tell I did) and applied some high temp grease, (sparingly) to the contacts for the shoes and, around the larger part of each roller.

I then re-installed them, slapped the drums back on with two lug nuts and then, adjusted the brakes to almost and even a tad bit of "touching" the drums. Finished installing the wheels and tires. Boy, that 600 lb. torque wrench I got off ebay sure works nice. Anyway, took the large beast out for a cruise this morning and EVERYTHING works flawlessly. All my gauges, my exhaust brake, the cruise control and more, work as good as new. As for the "Clunking" when the brakes were applied, GONE! Works as good as it did when it came from the factory.
Scott