Dreaded frame flex

rubio171

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RV LIFE Pro
Joined
Aug 3, 2023
Posts
24
Location
houston
Si I just noticed last time out that I’m getting a little bit of flex in my pin box and molding on left side front is moving a little on the side panel. I’m am going to pull the panel around the pin box off and add some reinforcements after I go inside and upgrade the lag bolts to bigger size and maybe add a few more. Anyone done anything like this and can offer some advise on how to reinforce?
 
Your forum profile shows you have a 2019 3811MS.

I am not well versed on causes and repairs for “frame flex” in Montanas. I have read and followed every frame flex thread in this forum since I joined in 2018. It seems to me that there are two issues that get pronounced “frame flex”, and they really should be separated.

1. Failures in the frame (chassis)
- Broken welds at various locations in the frame
- Broken or cracked steel frame members
- Broken welds allowing the tongue to move
- Broken welds in the floor joists
- Outrigger failures
- Bends in the rear frame cantilever…just to name a few

2. Aluminum stud weld breaks
- I have seen photos of the fix for this showing wood blocking inserted into some of the tube wall framing, to provide for better connections for screws.

I have seen videos of other brands adding bolts to secure the “house” to the chassis. I dont recall seeing the process detailed here.

I think Lippert has a process for measuring movement in the tongue of the frame. Have you measured yours? Have you looked inside the front compartments for broken frame welds?

It would be good if you could post photos of your concerns and get some help from forum members who have been through the issue and had the issue corrected. Do this before you remove panels…or you could search the forum to find threads describing similar failures to yours.
 
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If the flex is when you hook up the truck, I think lippert says something like 1/2 inch to 1 inch movement. This might be a little too much for what they said, I don't remember. When I had this, the dealer removed the whole front cover and went in and re-welded the joints and maybe added gussets. No problem after that.

I could tell something was wrong because the paneling on the side of my closet (in the overhang part of the front end) would bow out and pull out the small nails. Good luck.
 
Si I just noticed last time out that I’m getting a little bit of flex in my pin box and molding on left side front is moving a little on the side panel. I’m am going to pull the panel around the pin box off and add some reinforcements after I go inside and upgrade the lag bolts to bigger size and maybe add a few more. Anyone done anything like this and can offer some advise on how to reinforce?
We highly suggest you DON'T DO ANYTHING UNTIL you contact Keystone at 866-425-4369, give them the last 8 of your VIN, explain the situation, the concern and in many cases, Keystone is authorizing the repair at their expense, even on older units. They covered our "frame flex" repair on our 6 year old 3790RD. If you do anything and it's not correct or gets messed up, then you may be stuck with a very large bill that no one else will cover.

Keystone has guidelines and a policy on determining if it is flex. The flex is the result of broken welds between the Lippert frame and the Keystone Aluminum uprights. The fix is to take the entire front cap off and reinforce the side(s).

If you attempt to do a repair, that unless you remove the front cap and it's doesn't fix the issue, you may still pay $$$$$ for the proper fix.

Laura and Jerry Thorsell
MOC#19945
 
Your forum profile shows you have a 2019 3811MS.

I am not well versed on causes and repairs for “frame flex” in Montanas. I have read and followed every frame flex thread in this forum since I joined in 2018. It seems to me that there are two issues that get pronounced “frame flex”, and they really should be separated.

1. Failures in the frame (chassis)
- Broken welds at various locations in the frame
- Broken or cracked steel frame members
- Broken welds allowing the tongue to move
- Broken welds in the floor joists
- Outrigger failures
- Bends in the rear frame cantilever…just to name a few

2. Aluminum stud weld breaks
- I have seen photos of the fix for this showing wood blocking inserted into some of the tube wall framing, to provide for better connections for screws.

I have seen videos of other brands adding bolts to secure the “house” to the chassis. I dont recall seeing the process detailed here.

I think Lippert has a process for measuring movement in the tongue of the frame. Have you measured yours? Have you looked inside the front compartments for broken frame welds?

It would be good if you could post photos of your concerns and get some help from forum members who have been through the issue and had the issue corrected. Do this before you remove panels…or you could search the forum to find threads describing similar failures to yours.
We had the "dreaded frame flex" and were the first 5th wheel that Affinity RV Repair back in 2018. It's Keystone, not Lippert that makes the determination because it's the Keystone part that is breaking. Seen lots of repairs to other's 5th wheels, most done by Affinity. We've also personally seen cases where Keystone refused to cover the cost because owners thought they knew what they were doing and messed up. The average frame flex repair can exceed 5K. I see that your are just up the road from us here in Texas. We are based out of Bandera.

Laura and Jerry Thorsell
MOC#19945
 
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My Granddaughter works in the warranty repair/parts department at Keystone. PLEASE! DO NOT attempt any repairs yourself as this WILL VOID any coverage that Keystone would or will provide. They are aware of the problem, and in most cases are willing to provide coverages for any damage caused by frame flex even after the 3 year chassis warranty expires. PLEASE, just schedule an appointment with a local dealer for assessment, verifaction, and needed repairs.
 
We Noticed a crack in our camper right above the kitchen slide we have a Montana 361frl is this due to frame flex
 
My Granddaughter works in the warranty repair/parts department at Keystone. PLEASE! DO NOT attempt any repairs yourself as this WILL VOID any coverage that Keystone would or will provide. They are aware of the problem, and in most cases are willing to provide coverages for any damage caused by frame flex even after the 3 year chassis warranty expires. PLEASE, just schedule an appointment with a local dealer for assessment, verifaction, and needed repairs.
Why don't they re-engineer these at the factory?
 
Real (old type) frame flex is where the welds on the main frame - 10 or 12 inch I beams go up to the overhang. My rig had these welds crack right in the corner of the overhang causing the front area to sag and raise up when hitching/unhitching. The newer stuff is aluminum stud welds breaking in the walls. And now I am reading here about somehow the I beams themselves are twisting (but I am not clear on this).
I had the old frame flex in 2012, and the new aluminum stuff on the front AND rear maybe 6-8 years ago. Perhaps dragging the rig(s) to Alaska twice had something to do with it! LOL:oops:
 
Why don't they re-engineer these at the factory?
Keystone has been re-working the issue and trying new ways to prevent the flex. So far, units that had the flex, Keystone has found ways to fix the various ways the flex failures are happening. Not all failures are exactly the same. Our rolling earthquakes sometimes just shake, rattle and roll too much. Also, what must be considered is how much weight we owners put in our 5th wheels because many owners do overload their units, whether they admit it or not. It matters too on how owners tow their units over our road systems. Several factors to take into account and we know that Keystone is trying, maybe not just fast enough for many.
 

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