P30 Rear Shock pulled from Chassis

[GLWilliams58]

Hi. I am new to this forum and new to the P30 that came under my 2004 Admiral SE that I bought this past week. This is my first Motorhome and I have a lot to learn.

Crawling under my new rig yesterday I found the driver side rear Bilstien shock had pulled out of the bolt and bushing and away from the chassis. It is still connected to the axel, but the mount there is twisted. This leaves the shock pointed inwards toward the center line of the vehicle, but still up above the drive shaft.

So, I took it back to the dealer to be fixed, but I am wondering what would have caused this to happen. I saw no indication of any other damage that might occur with a blow out. This coach has 15000 miles on it and all the tires look to be the same condition.

Is this something that others have experienced?
Would this affect the vehicle alligment? Is there anything else I need to get checked out while they are fixing this? If the mount is twisted, should it be cut off and replaced with a new one, or is bending it back in shape acceptable?

Thanks for your thoughts.

Greg

[GLWilliams58]

Hi. I am new to this forum and new to the P30 that came under my 2004 Admiral SE that I bought this past week. This is my first Motorhome and I have a lot to learn.

Crawling under my new rig yesterday I found the driver side rear Bilstien shock had pulled out of the bolt and bushing and away from the chassis. It is still connected to the axel, but the mount there is twisted. This leaves the shock pointed inwards toward the center line of the vehicle, but still up above the drive shaft.

So, I took it back to the dealer to be fixed, but I am wondering what would have caused this to happen. I saw no indication of any other damage that might occur with a blow out. This coach has 15000 miles on it and all the tires look to be the same condition.

Is this something that others have experienced?
Would this affect the vehicle alligment? Is there anything else I need to get checked out while they are fixing this? If the mount is twisted, should it be cut off and replaced with a new one, or is bending it back in shape acceptable?

Thanks for your thoughts.

Greg

[Bucky1]

When I replaced the shocks on mine, one did the same thing. The parts store replaced the shock, and it never happened again. Wish I could give more of a warm fuzzy on this one. If the mount is twisted, that won't help.

[DriVer]

The chassis that you are referring to is a P32 however for the purpose of this post and for your information going forward you can consider your motorhome to be a "P Series" chassis.

We have seen this in the past on iRV2 where the rear shock tower has separated from the chassis. This is caused by at minimum 1 weak or failed rivet in most cases where the vehicle may have been over loaded or close to its GAWR(rear) or GVW. It is unlikely that the tower itself it damaged or twisted unless it really got beat up. The tower is robust gauge steel and it may be sound enough to just reattach it to the frame.



Photo By: "Jestme13"

More information here: Broken Rear Shock Mount

The resolution is to go to a Workhorse Service Center to have the problem fixed or failing that a good heavy duty truck shop. Reattaching the shock tower is accomplished using appropriately sized Grade 8 NF or better bolts, secured using nylon lock nuts or Nylocks and torqued to the capacity of the fastener.

Subsequent to this repair you no longer will have any issues. If the tower is damaged, resourceful shops will be able to replace or repair the tower.

Let us know how this issue was resolved.

[GLWilliams58]

Thanks for the insite Driver. The photos you show are helpful in explaining what could have happened, but the end result is a little different.

Whereas your pictures show the upper shock mount still attached to the top of the shock, my top mount is still in place on the chassis with the shock bushing and the bolt and washer intact. I did not inspect the top mount to see if it was pulling away from the chassis, but the bottom mount on the axel is severely bent.

The shock itself, appears complete except for the top bushing and the bolt and washer.

[Jestme13]

[Bucky1]

That is what I have seen on mine. Pulled right off of the bushing.

[Joe Gilbert]

When I added Bilstien's to my P30 (about 1989) Bilstein sent a notice with the shocks that the rear frame mounts required reinforcing. I beefed up my mounts before adding the shocks.

So!! Bilstein knew of the weak mounts. Where did you purchase your shocks?

[GLWilliams58]

Joe, according to the manual, Bilstiens are stock for that year. The rig has 15000 miles, so I suspect they are straight from the factory. This was the first time I ever drove a motorhome, so I thought it drove ok. But as you can imagine, the ride must leave a lot of room for improvement. The Work Horse manual says Bilstein provides the front and rear shocks and the stearing stabilizer.

Bucky1, you understand exactly what I am saying. The shock actually pulled off of the bushing. Everything else stayed in place. What was your diagnosis? How did you notice the problem? Did you replace both rear shocks? Did you have any damage to the mounts? Where they stock shocks? Did Bilstein replace them at no charge? Has it happened again since then? I am very curious about your situation. Thanks in advance for the reply.

[Bucky1]

Mine was pretty crude. I looked under there because I needed to do something else, and the shock was hanging there. It was a CarQuest heavy duty shock, and when I took it back, they gave it a strange look, and said sorry and gave me another one. The mount looked fine, although I would have made it a bit stouter if I had designed it. It never did it again, so I guess it had something to do with the bushing in the shock. I can't imagine I installed the second one differently than the first. Mine hadn't been on there for more than a couple 200 mile trips when I noticed it. I guess it was just a fluke with a loose bushing. I would take a run at Bilstein for replacing that shock.(if they aren't very old) If you are worried about the other side matching, offer up to buy one if they will give you the other. That would sound fair to me. I had never seen a shock do that before or since that. Neither had my mechanic friend.

[GLWilliams58]

Thanks Bucky1.

This one seems kind of like a fluke as well. Clearly there is a very strong presssure point where these shocks attach. In this case it seems as though the shock bushing was the weaker link, which hopefully means the mounts are strong.

Seeing as this is all being taken care of by the dealer, I won't be directly involved with the plan to fix it until I see what they do, and see if it is acceptable when I get it back.

This P series sits very low in the front even with 90lb in the inner spring air bags. My hope is that having two shocks working in the back will pull the back down a little and level things up. I should know in a few days how it turns out.

Thanks again for your thoughts and I welcome any other input or insight to this.

gw

[Bucky1]

No problem. I hope all goes well. I'm not sure that it will help the front ride height though. You may want to ask them if you are within spec on front ride height.

[rgrstndgby]

Greg, Im not real familiar with that chassis, but 2 questions, first, is the "snubber",the item that would limit/prevent, "Bottoming out", (generally on the lower A Frame,) in place, and if it is, and it appears ok, is the shock free to extend, and contract. Ive seen a 'frozen shock' produce the same results on other vehicles..rgr...

[GLWilliams58]

I got the coach back from the shop today and inspected the repair. It appears they heated the mount on the axel and beat it back into place (nearly). They remounted the shock to the chassis mount (which shows no sign of pulling away from the chassis). However, upon close inspection, with all the banging it must have taken, they have cracked the lower mount on the axel. I can nearly put my little finger in the crack. I have to take it back to the shop again.

It would seem like they may want to just weld this crack, but as mangled as the mount is now, I would think the proper thing to do is cut the entire mount off the axel and weld on a new one. I would not think that this is something that anyone would want to do without removing the entire rear axel. Those gas tanks are pretty close.

When I return to the dealer and demand they fix it, does it seem unreasonable to insist they cut this off and weld on a new one? Could the small weld on the crack be satisfactory? If this was a warranty job at another dealer what type of repair would be required by WorkHorse?

Thanks for your help.