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Rear air bags look askew after rough highway


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I was looking things over after a rough section of highway and noticed my rear air bags were a little crooked. When I looked at the air bags before I think I would have noticed this. The wheel well liner is still missing after I blew a tire a couple weeks ago, so the air bags are easily visible now. 

I just had new tires installed, and I didn't really look that close after that. When installing the tires, I put the hydraulic jacks down so they could just jack up the suspension a little to get the tires off the ground. Is there something centering inside the air bags that might have shifted? Is this more likely related to the trailing arms?

The strange thing is the coach drives reasonably well and doesn't feel any different than before.

The pic on the left is normal ride height, right is aired down.

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The front looks normal.

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IMG_8590.jpeg

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Obviously, either the top frame that the air bag is mounted to has shifted one way or the bottom frame has shifted in the opposite direction.

I would be looking at the alignment of all frame members and arms.

Or did it actually come from the factory that way?

Edited by Dr4Film
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10 minutes ago, Jerry G said:

Can't help with air bags, but what highway did that?

For 15 miles of I-81 north of Binghamton, NY, some asshole road crew recently "fixed" the broken asphalt over the concrete expansion joints with what is effectively speed bumps. That has to be the worst section of highway I've ever seen. 

11 minutes ago, Dr4Film said:

Obviously, either the top frame that the air bag is mounted to has shifted one way or the bottom frame has shifted in the opposite direction.

I would be looking at the alignment of all frame members and arms.

Or did it actually come from the factory that way?

I feel like I would have noticed that last week when the blowout took out the wheel well liner, because I was looking to see if anything else was damaged, specifically air bags and lines. 

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Guest toastmn

Check your control arm bushings.  Mine were disintegrated after a rough stretch of highway.  The polyurethane bushings are junk from my vintage.

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Edited by toastmn
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Turns out at least one trailing arm bushing is gone. Are truck service shops likely to have these? Or do they have to be ordered from somewhere?

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For comparison, the other side still looks pretty centered.

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Guest toastmn
5 hours ago, jimc99999 said:

Turns out at least one trailing arm bushing is gone. Are truck service shops likely to have these? Or do they have to be ordered from somewhere?

IMG_8612.thumb.jpeg.ad6c04b1179ec4be37e08a83b72d7592.jpeg

For comparison, the other side still looks pretty centered.

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I sourced from 3 different vendors

P/N#'s

MO10000

86820

01803668

My Coach has 20 of these bushings.  10 in the rear, 10 in the front.   You can't get away with simply replacing the bad one.  Once one end is good, it thrashes the other end.  Ask me how I know!   I found the best value to be this bushing.

Suspension Bushing Cartridge for Monaco, Holiday Rambler and Other Roadmaster Chassis Diesel Motorhomes | 01803668 (findmyrvparts.com)

 

They are 3" wide, 2" diameter, 7/8" bolt, and are an interference fit.   I had to freeze the bushing, and heat up the control arm, and still mushroomed a few.   Then I bought a 2" cylinder hone and that made all the difference.

Amazon.com: Brush Research 2" (51mm) Flex-Hone Cylinder Hone Tool 120 Grit (Silicon Carbide) : Industrial & Scientific

To get mobile, I made a bushing using hot glue.  Made it 1200 miles home with it, and looked good as new when I removed it a year later!

20190413_162603 (1).jpg

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Edited by toastmn
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1 hour ago, toastmn said:

My Coach has 20 of these bushings.  10 in the rear, 10 in the front.   You can't get away with simply replacing the bad one.  Once one end is good, it thrashes the other end.  Ask me how I know! 

I haven't examined the suspension that much yet, but I thought there were only 2 trailing arms per side, so that would be 8 bushings per end? Where are the other 2 bushings? Your Windsor is the RR8S chassis too, right?

I don't have a good place to work on the coach, no access to air tools at least. Is it possible to get those bolts loose with a breaker bar? 

1 hour ago, toastmn said:

They are 3" wide, 2" diameter, 7/8" bolt, and are an interference fit.   I had to freeze the bushing, and heat up the control arm, and still mushroomed a few.   Then I bought a 2" cylinder hone and that made all the difference.

Once you honed the inside of the sleeve where the bushing goes, did you still have to heat the control arm and freeze the bushing? Can you use a lubricant when installing those bushings?

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Guest toastmn
13 minutes ago, jimc99999 said:

I haven't examined the suspension that much yet, but I thought there were only 2 trailing arms per side, so that would be 8 bushings per end? Where are the other 2 bushings? Your Windsor is the RR8S chassis too, right?

I don't have a good place to work on the coach, no access to air tools at least. Is it possible to get those bolts loose with a breaker bar? 

Once you honed the inside of the sleeve where the bushing goes, did you still have to heat the control arm and freeze the bushing? Can you use a lubricant when installing those bushings?

The trackbar uses the same bushings.  Only do 1 arm at a time.  I serviced 6 of them in the dirt where I was camping over the the course of a week.  It's a big job  but doable.  I have a 44" 3/4" breaker bar for breaking loose lugnuts.  I bought a 1 5/16"? combination wrench for the other end and used the frame to stop it from rotation.  An air hammer is crucial if the 3/4" bolt is stuck and it has to be cut (which most of my bolts had to be cut).  A GOOD balljoint press (snapon) is needed if a real press is unavailable.

With the hone, lubrication would be sufficient if you can't freeze them.

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Edited by toastmn
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1 hour ago, toastmn said:

A GOOD balljoint press (snapon) is needed if a real press is unavailable.

At $800 for a snapon balljoint press this might be a job for a shop. Although I'm currently parked next to my client's shop and I'm pretty sure they have a press in there. I'll check tomorrow and see what they have for impact wrenches and tools. They only work on their drag bike, not their truck, so they may not have big tools. But they did have a big press they were using on clutch plates a few years ago.

I've seen people mention using blocks of wood for suspension/frame spacer jacks for working under the vehicle, would 8-10" sections of 4x4 hold the weight? I guess 2 spacers per side, front and rear of subframe?  Once a trailing arm is pulled, the suspended frame could shift, seems like using a spacer might not actually be safe in this case?

Edited by jimc99999
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Guest toastmn
2 hours ago, jimc99999 said:

At $800 for a snapon balljoint press this might be a job for a shop. Although I'm currently parked next to my client's shop and I'm pretty sure they have a press in there. I'll check tomorrow and see what they have for impact wrenches and tools. They only work on their drag bike, not their truck, so they may not have big tools. But they did have a big press they were using on clutch plates a few years ago.

I've seen people mention using blocks of wood for suspension/frame spacer jacks for working under the vehicle, would 8-10" sections of 4x4 hold the weight? I guess 2 spacers per side, front and rear of subframe?  Once a trailing arm is pulled, the suspended frame could shift, seems like using a spacer might not actually be safe in this case?

You can buy a 12 ton HF press for much cheaper.   I used 6x6 blocks of wood under the axle as a fail safe and used the jacks to raise lower the coach to find the sweet spot where the control arm is happy.  None have any adjustment.  A helper at the jack control is best, but I was able to use a hydraulic jack to raise/lower the axle independent of the coach.  I used a 6" grinding disc on my 4.5" grinder.  You need fresh discs, and the extra reach to cut through the bolt.   I always removed the nut first, then tried to rotate the bolt with the breaker bar to break it free from the bushing/mounting bracket.

 

3 hours ago, det944 said:

Great idea for the temp repair using hot glue gun... genius!

Thanks!   My idea was to use a 2" wood dowel, but my friend suggested the hot glue,  worked awesome!

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17 hours ago, toastmn said:

Currently Veurinks (findmyrvparts.com) does not have any of these bushings. They said they're waiting on their big stock shipment but they don't have any eta.

And a truck parts supply chain (fleetpride.com) can't find any ATRO MO10000 or anything that cross-references with it. The parts guy is searching for other applications that use the same size now and will let me know. 

We might all have to make bushings with hot glue sticks...

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Guest toastmn
21 minutes ago, jimc99999 said:

Currently Veurinks (findmyrvparts.com) does not have any of these bushings. They said they're waiting on their big stock shipment but they don't have any eta.

And a truck parts supply chain (fleetpride.com) can't find any ATRO MO10000 or anything that cross-references with it. The parts guy is searching for other applications that use the same size now and will let me know. 

We might all have to make bushings with hot glue sticks...

Try calling Jim.  He was very knowledgeable but his price point x20 made it difficult to justify. 

Screenshot_20220623-094013_OneDrive.thumb.jpg.5c887b5810b73e9346a55db671bc9ba0.jpg

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