Pinbox Frame Flex (Again) in So. Ca.

[Bones]

The bolts should be 5/8-11 bolts. The current ones are probably grade 5 bolts which are fine but if you want stronger bolts you can opt for grade 8. I have grade 8 on my pin box.

 

[mlpeloquin]

Bones is correct. Upgrade to grade 8. The bolts won't see the amount of shock and vibe that the old ones did. The cost difference is small. I also added two bolts, one on each side, because I could. My air pressure is 75 lbs for the air bag. You can start from there and adjust as needed. As you pull the setting will be below the arrow and when you stop or slow down it will rise above the arrow. Just driving down the flat road the arrow should just fully show. You will love the hitch. I also added an aluminum bar stock shim so the welds on the pin box would not be under tension. The Flex Air is about 1/8" narrower the the original equipment one. If you view the installation video on U-tube, watch the sides pull in as they gun the bolts on. I torqued mine.

 

[wdk450]

Gang:
I wanted to report in and share some photos on the impressive gusseting pieces installed by Heartland. I also wanted to report that the air ride pinbox is now installed, and the rig ride is much smoother. Complete details of the repair will be on a future post after some more interaction with the RV repairer.

As I stated above, I found the size and thick metal of the pinbox and frame overhang gussets to be impressive. The welds were beady though, and not up to the type of welding you see on the pinbox itself. My RV repairer went over all of the welds, but their welds didn't look much nicer. Here are the photos:
Left frame riser gusset. Right frame riser gusset.
Left side of pinbox attachment plates Right side of pinbox attachment plates

 

[wdk450]

Fellow Heartlanders:
Here is an update and request for suggestions on my ongoing (since June 6th) pinbox frame flex repair. After the independent repairer told me that they found nothing wrong with the pinbox frame area, and suggesting I upgrade to the Lippert Air Ride pinbox (which I had them install), about July 11th I towed my rig off to the Menifee, Ca. Thousand Trails (about 50 miles away) for storage. Upon arrival at the park, I found this big crack in the fiberglass between the bedroom slide front lower corner and the hitch overhang:

I towed it back to them the next day, and they promised to fix the crack promptly. After removing the front overhang fiberglass again, a crack was found in the metal support tubing at the site of one end of the fiberglass crack.
Further investigation revealed that there is a major crack in the underlying metal framework underlying the crack in the fiberglass from the pinbox overhang to the lower front corner of the bedroom slide. I am sorry to report that I had the cellphone camera lose the photos I took of the metal crack under the sections of fiberglass that have been cut out for the repair. My repairer has had a piece of 3/16 (?) inch steel fabricated to bridge over this structural crack. I have had ongoing unfulfilled promises of completion of the work, but can't tow it away from this repairer in the condition it is in. I will work with them on that this week.

What I need is opinions from the combined knowledge of the HOC forum on the best way to repair this, and to make big 5th wheel owners aware of this weak spot in the usual design of large 5th wheels.

I also plan to call Heartland service (and maybe Lippert) tomorrow to consult on this problem. I am thinking that like my previous I-Beam frame flexing at the axles, this structural failure is not all that unheard of in big 5th wheel RV's. I will do a Google search on this, too.

Thanks for all the anticipated help (and sympathy) from the Heartland family. Luckily, I have family in the area with guest rooms for me to stay in while my fulltime residence gets eventually repaired.

In Beaumont, Ca.

 

[Bones]

I'm sorry to see this. I am assuming all the extra bracing they were doing unfortunately may have revealed a week spot. I have been pondering the way the frames are made and have come up with a newer design that I think would serve the industry better but I would need mula to make that happen then lippert would probably put me out of business.

 

[JohnDar]

Maybe it's a good thing we don't travel much with ours, other than 400 miles round trip each summer to our seasonal site. We had the frame repairs done by our dealer the first year we had it. So far, it "seems" to be OK.


Sent from my iPhone using Tapatalk

 

[mlpeloquin]

Bill your initial frame flex was really a bad case. Perhaps it transferred a lot more stress to the weakest area in the frame which is where the bedroom slide is. It just takes a very small micro crack and then repeated pounding from the road to have it propagate through the entire length across. It would be nice if the frames in this area could be beefed up. You notice that there are not any reported problems on the non slide side of the fifth wheels. Cannot see what is on the other side of the frame, but to put a sister piece of metal and weld it on the other side all the way up would be my first thought. If it is extruded metal, cut it out and put in a heaver gauge.

 

[wdk450]

Gang :
Here is a follow up to my post #24 on this thread. I made yet another visit to the RV repairer today, literally begging him to have it done by Friday when some big time family medical problems are about to hit (scheduled knee replacement surgery for my sister who only has 1 guest room). Anyways, I was able to get some digital photos of the frame damage underlying the fiberglass crack. Here is the 1st one showing the overall big crack: The biggest problem is the small bar at the top of the photo with the crack in it is the bottom support for the bedroom slide. The repair guy wants to weld the crack but is very scared of catching the rig on fire. He says he needs a special welder tip to do the job.

Here is a little bigger photo of the entire area that has the fiberglass cut out:

Any experienced welders out there with any suggestions??

 

[Bob&Patty]

Bill, it looks like there is an other frame member above the crack. I don't see any reason that the crack cannot be welded and then a "fish plate" can be welded to both sides of the frame at that point to join both frames together. There are many ways to keep the heat from welding away from any wood structures. JMO

 

[Bones]

I think at this point more thought should be put into the repair and remove the slide as well as the flooring above the pin box area. What ever you do to one side you should do to the other side. I think the inner frame should be cut away here and plates welded on the interior of this cracked frame then weld the crack and grind it down flat. Once done then weld in a new section to replace the frame section that was cut. After all that the frame on the other side should have plates welded. After all of that has been completed you should add new framing members that go from the pin box area all the way back to the sections attaching to the I-Beam supports. Take the unit out after that and test for frame flex

- - - Updated - - -

I should also note that I'm not sure if this is the framing of the wall we see or the steel framing of the trailer. I am assuming it is the steel framing of the trailer. Another thought to fixing this is to change the look of the trailer a bit by using aluminum or painted steel in the nose on the side instead of fiberglass.

 

[ray587]

I think at this point more thought should be put into the repair and remove the slide as well as the flooring above the pin box area. What ever you do to one side you should do to the other side. I think the inner frame should be cut away here and plates welded on the interior of this cracked frame then weld the crack and grind it down flat. Once done then weld in a new section to replace the frame section that was cut. After all that the frame on the other side should have plates welded. After all of that has been completed you should add new framing members that go from the pin box area all the way back to the sections attaching to the I-Beam supports. Take the unit out after that and test for frame flex

- - - Updated - - -

I should also note that I'm not sure if this is the framing of the wall we see or the steel framing of the trailer. I am assuming it is the steel framing of the trailer. Another thought to fixing this is to change the look of the trailer a bit by using aluminum or painted steel in the nose on the side instead of fiberglass.

What we are looking at here is the aluminum wall framing. It sits on top of a lip that is part of the steel framework. If this aluminum is cracking the steel framework behind it is probably cracked too.

 

[wdk450]

Well, I just got the call this morning that the trailer is "fixed". Since I assume the fiberglass is back on over the metal repair, unless the repairer has pictures, I don't know how well it was fixed, or if it will hold up. I just know that I am out $5k, and the use of the trailer for 2 months while I am fulltiming. My sister, who just went through breast cancer treatment, had her husband of 11 years suddenly leave her (with a new car to pay for and a house they have been in just 1 year), with very little income, and a total knee replacement next week; needs me nearby. Most of the time I will be in her guest room, but next week her daughter is flying in to help care for her for a week, and my other sister is coming for 2 weeks the end of August to help. I need to be living in my trailer both of those time periods to make the guest room available. The Menifee Thousand Trails is about 35 miles away, and has both long term and short term storage.

I went through a BUNCH of broken promise completion dates with this guy, and if the trailer was towable, I would have the work completed somewhere else (if I could come up with the money).

Some prayers for me, my sister, and the of the repair to hold up would be appreciated.

In Beaumont, Ca.

 

[Bones]

Well, I just got the call this morning that the trailer is "fixed". Since I assume the fiberglass is back on over the metal repair, unless the repairer has pictures, I don't know how well it was fixed, or if it will hold up. I just know that I am out $5k, and the use of the trailer for 2 months while I am fulltiming. My sister, who just went through breast cancer treatment, had her husband of 11 years suddenly leave her (with a new car to pay for and a house they have been in just 1 year), with very little income, and a total knee replacement next week; needs me nearby. Most of the time I will be in her guest room, but next week her daughter is flying in to help care for her for a week, and my other sister is coming for 2 weeks the end of August to help. I need to be living in my trailer both of those time periods to make the guest room available. The Menifee Thousand Trails is about 35 miles away, and has both long term and short term storage.

I went through a BUNCH of broken promise completion dates with this guy, and if the trailer was towable, I would have the work completed somewhere else (if I could come up with the money).

Some prayers for me, my sister, and the of the repair to hold up would be appreciated.

In Beaumont, Ca.

prayers to you and your family

 

[ray587]

Praying for you and your sister. You know the old saying "when it rains it pours". Hope everything works out for the best.

 

[danemayer]

Adding you to the prayer list Bill.

 

[jhardin]

Well, I just got the call this morning that the trailer is "fixed". Since I assume the fiberglass is back on over the metal repair, unless the repairer has pictures, I don't know how well it was fixed, or if it will hold up. I just know that I am out $5k, and the use of the trailer for 2 months while I am fulltiming. My sister, who just went through breast cancer treatment, had her husband of 11 years suddenly leave her (with a new car to pay for and a house they have been in just 1 year), with very little income, and a total knee replacement next week; needs me nearby. Most of the time I will be in her guest room, but next week her daughter is flying in to help care for her for a week, and my other sister is coming for 2 weeks the end of August to help. I need to be living in my trailer both of those time periods to make the guest room available. The Menifee Thousand Trails is about 35 miles away, and has both long term and short term storage.

I went through a BUNCH of broken promise completion dates with this guy, and if the trailer was towable, I would have the work completed somewhere else (if I could come up with the money).

Some prayers for me, my sister, and the of the repair to hold up would be appreciated.

In Beaumont, Ca.

I'm just curious, does your 5th wheel hitch head tilt side to side and so forth?

 

[JeepingJason]

I'm just curious, does your 5th wheel hitch head tilt side to side and so forth?

Just wondering what is normal .I measured my pin box today from the tip of the pin box to the h in big horn . Hooked up then on the jacks and got 3/4 inch difference . Is this normal or do I too have this problem 2009 bighorn 3050 rlThanks. Danny

 

[mlpeloquin]

Just wondering what is normal .I measured my pin box today from the tip of the pin box to the h in big horn . Hooked up then on the jacks and got 3/4 inch difference . Is this normal or do I too have this problem 2009 bighorn 3050 rlThanks. Danny

Does your side trim pull away from the side or your fiberglass side cracking? Does the skin by the hitch form a wave or move? If not, most likely not. But keep an eye on it. I do mine all the time now. Metal will bend under tension like a spring. Two thousand plus pounds will bend metal. How much depends on the structure. I put on a Trailair Flex Air hitch to all but eliminate the shock of the road being passed onto the frames. My frames were ok, but the fasteners that held them together sheared off on the left side. The left slide side is the weakest point on the entire frame structure. That is where Bill's crack formed. If something is going to happen, it will be the Lippert frame with the hitch mount or the front slide area. If you are worried about the frame, you can remove the side trim form the entire front, the screws holding the fiberglass on, and then pull the fiberglass away and expose the frame for inspection. You do not have to remove the hitch, but do need to remove the shroud the covers the hitch. Put old blankets down to protect the fiberglass skin. Putting it back together should not take long and calk well.

 

[wdk450]

Yes, my hitch tilts in both directions.

 

[wdk450]

3/4 inch isn't much. Keep an eye on it. If you are not the 1st owner, Heartland probably WON'T do the repair for free. Either way it would be at their Elkhart, In. factory ONLY. Call Heartland service with your VIN if in doubt - maybe the previous owner (if any) had this fixed.

Newer Bighorns (2010 and later?) have a more gradual curve to the sides at the front storage compartment, then do the older Bighorns with right angle sides. But this is all about additional FRONT pinbox framing bracing, not the side near the bed slide like I just had problems with. I think that this near slide load bearing distance is very small, but looking at other 5th wheels most of them has this narrow gap. A few brands have about double the gap, though.

BTW, my sister got through her knee replacement, and has no recurrent signs of the breast cancer. Thanks for all the caring and prayers from the Heartland community!!!