2020 Grand Design Momentum Body & structure Problems

I'm submitting this report on our RV because we are discovering we very likely have an issue with the frame which is causing over flexing when it is being towed. This has caused damage inside the RV where the trim and cabinetry are damaging the walls due to more movement than should be occurring. We have notified the manufacturer, Grand Design, for guidance as we've read this could be caused by broken welds in the frame. They requested we send them photos which we have but are still waiting for information back from them. At this point we are concerned that the RV may not be safe to use until we can discuss in more detail the issues we are having and how they can't be fixed if possible. We are aware this is a known issue with this particular model RV. We were told about a TSB that suggested we check to see if the bolts were loose in the front of the unit where the wall and frame meet. We did this and they were loose so we had them replaced with the suggested larger size bolts listed in the TSB. After this was done we monitored the walls to see if we were still getting movement on the walls based on marks we made after the bolt were replaced and unfortunately we still did. Our understanding is the whole front panel of the RV has to be removed so the welds can be inspected and determined if any are broken or compromised and then determine if they can be repaired. Before doing this we want Grand Design to send us information on what to look for. Unfortunately our RV is over the 5 year extended frame warranty they provided so we don't think they will cover the costs although I think there should be compensation if it is determined the frame they used in manufacturing this RV was not strong enough to handle the weight.

NHTSA ID

11745588

Incident

Apr 15, 2026

My Momentum 5th wheel is experiencing frame flex and wall separation . This condition is causing damage to the interior side wall adjacent to cabinets in the bedroom wall. Frame and or wall assembly is excessively moving in transport and during hooking and unhooking from the unit. Unit will be inspected in the near future by a Grand Design authorized service agents. The condition is further degrading the safety of the unit with each use in transit.

NHTSA ID

11731307

Incident

Oct 25, 2024

The contact owns a 2020 Grand Design Momentum. The contact stated that upon hitching the trailer to the vehicle and driving, the entire frame of the trailer was flexing. The contact stated that the failure caused the laundry room door to fail to latch because the attached wall was damaged. The contact stated that the internal trim screws had become loosened, and the trims were detaching. The contact stated that the front side of the frame, underneath the fifth wheel, was cracked on both the passenger's and driver's sides and had significantly fractured and detached on one side. The RV was taken to Bailey's Towing & Auto Body, where it was determined that the frame was flexing excessively. The RV was not repaired. The manufacturer was notified of the failure, but no assistance was provided. The contact related the failure to NHTSA Action Number: PE24029 (Structure). The failure mileage was approximately 10,000.

NHTSA ID

11697120

Incident

May 15, 2025

Mileage

10,000 mi

The frame of my trailer sustained damage due to flexing from poor design. I was lucky and noticed some loud noises when transitioning weight to the king pin on the truck. A lot of creaking and groaning. Because of all of these noises and what I had read online, I had the trailer inspected. The inspection found the frame moving within the structure when the weight transitions from the stabilizers to the king pin. Additional damage was a crack in the structure that holds the wall to the frame and many bent gussets that are designed to give the structure strength. This design is substandard. I understand the whole thing is designed to work as a whole to provide strength, but there are weak areas in this design. First is the use of lag bolts into a soft wood as a method of connecting the frame to the wall structure. This needs to be into metal or aluminum allowing the use of bolts and a thread locking compound to prevent loosening. Lag bolts into wood on a structure designed to withstand dynamic movement of towing is inadequate. This will always loosen over time transferring the load to other areas of the structure and the damage many are seeing. My trailer has been repaired, but I'm not sure if the new gussets and additional lag bolts will be enough because they are still using wood as a structural component. My trailer is a 2020 and the 5 year warranty will expire in September. I'm not sure where I will be after that when the next repair comes. I don't have a lot of pictures because I was out of town when they did the inspection. You can see the break in the wall support showing that the wall was moving after is separated from the frame. The pictures show how this bent the gussets that are designed to give the structure support. Like I said, I saw this problem online and asked for in inspection before I had real problems. If I had waited, the damage would've been much worse.

NHTSA ID

11663007

Incident

Aug 1, 2024

Frame issues with the gooseneck area of the RV. We've got lots of movement with the RV in these areas where it connects with the towing vehicle. We have had lots of movement in the front nose area of the RV causing substantial movement evidenced by interior and exterior cracks and noises when pulling. We have taken the RV to a repair facility and the manufacturer has denied making repairs to make the RV safe.

NHTSA ID

11650645

Incident

Jul 5, 2024

The vehicle is experiencing severe frame flex causing the 2 passenger side entry doors to open while traveling down the highway in addition to rubbing the interior cabinetry against the side walls of the interior and causing the furnishings to be damaged. When the doors are wide open items can easily fly out of the vehicle while traveling making my personal items projectile hazards. The vehicle has been diagnosed for frame issues by an authorized repair facility "Busted Knuckle RV" in Las Vegas Nevada. Grand Designs did not authorize the repair facility to perform the necessary inspection work and Informed the shop that I would be liable for the cost of the initial tear down inspection that can average $5,000.00 The unit has had saw dust and rub marks on the interior since we first purchased the unit and transported it from Texas to our home in Arizona. We were not sure what caused this rubbing of the furniture on the interior and were later informed that this is caused by extreme frame flex or failure. The pinch style moldings that cover the seams on the front cap of the rv have loosened while driving and flap in the wind while traveling down the highway, I have since been forced to apply silicone to keep these in place. This style of molding is designed to stay in place without having to apply any adhesive to them. The doors have opened while on the highway on several occasions causing great concern considering we only use the vehicle approximately 6 trips per year.

NHTSA ID

11648150

Incident

Mar 4, 2023

On walk through rear awning flew off in slight breeze, took 4 years to get repaired with covid and parts availability, could have just as easily came off on the road, had two 3/4'' screws holding it on and into skin, not frame. Upon looking at bedroom night tables gap at front cap found rub marks on wallcovering and sawdust from rubbing/flexing cabinets from perceived frame flex. back garage man door would open by itself while traveling if deadbolt not used , front man door sticks and screen door has to be opened separately with considerable force. Will be opening a claim for flex frame with Grand Design

NHTSA ID

11630639

Incident

Dec 11, 2024

2020 Grand Design 395M I am writing this with concerns over possible Frame or Structure issues in our unit, the following is a list of objects of concern. 1.Screws attaching underside of nose cap to upper deck breaking 2.Wall next to stairs entering the upper deck showing signs of movement and wearing on wallpaper. 3.Support uprights on left and right side between night stands and upper cabinets are moving and wearing on wall. 4.After a day of travel sawdust is appearing on tops of nightstands. 5.Wallpaper and wall wear on right side of bedroom floor behind entry door near carpet that covers lag screws. 6.Excessive creaking coming from bedroom slide wall when coupling and uncoupling from tow vehicle. 7.Exterior entrance door will not stay closed unless deadbolted (including cargo door) doors have opened during travel. 8.Interior door jams are widening. 9.Pin box is sinking into frame when put in load position on vehicle (suspect frame failure)

NHTSA ID

11630352

Incident

Jun 1, 2023

We have been living full time in our RV since Nov, 2022. We just brought our Grand Design Momentum M-381 in for the front cap replacement as there was frame flex over the past several months that we didn't realize was happening and there were cracks in the top of our cap. Let me explain, we saw evidence of "something" happening like the bedside tables rubbing against the wall and saw dust, the outside cap moldings/weatherstripping flapping in the breeze as we drove down the road, squeaking of our bedroom floor and eventually a separation of the wall at the floor by our bedroom door. We youtubed these issues and came up with several videos and realized we needed to remove the carpeting and see if we had the lag bolt issues and boy did we! We had 2 that were rusted and half way out, one that was sheared off and one that was hanging loosely. We took it into a dealership in LA where they did the frame flex evaluation for Grand Design and it was determined to change out the lag bolts for 1/2 inch ones on both sides of the superstructure. Long story short, the lag bolts worked their way out after one short trip and we were told to bring it into the dealership where they were told by Grand Design to epoxy the lag bolts in, that was in July 2024. At the same time we ended up with cracking in the front cap by the roof and that was scheduled to be replaced. When we brought the RV in for the cap replacement on Nov 7th we mentioned one lag bolt was working back out and Grand Design asked for another frame evaluation and that's when they found out that the lag bolts they epoxied in just 3 months ago were tearing through and the frame. After further testing and removal of the under cap area there was evidence of complete crack of the superstructure frame on the drivers side and evidence of welds in other areas of the superstructure that had cracks in the steel and aluminum. We're waiting to hear back from Grand Design how we are to move forward.

NHTSA ID

11624240

Incident

Nov 7, 2024

Frame failure issues diagnosed on the camper in 2023. We were not apprised of how serious the frame failure was or provided photos of the issues, so we are not sure how extensive the issue was. Repairs were performed by a Grand Design dealer prior to the Technical Service Bulletin being released by Grand Design. The repairs being performed prior to the TSB leaves us somewhat skeptical that they were performed according to Grand Design engineer specifications. Post repairs, we have had some of the same symptoms recurring again (sawdust after every trip, furniture movement, garage wall separation, front cap filon separation, door opening during travel (previously reported to NHTSA), indicating that perhaps the frame issues are persisting or recurring.

NHTSA ID

11624047

Incident

Jan 2, 2023

11/15/2023: Kitchen slide of the RV partially opened while traveling down the road. My husband does have video of this occurring as we have a camera system installed on our RV. 6/25/2024: Kitchen slide of RV "raised up" and landed on an island drawer pull while traveling down the road. The slide could not be "lifted off" of the drawer pull and we were forced to activate the slide and allow it to travel out, causing damage to the drawer pull and drawer rails.

NHTSA ID

11620697

Incident

Nov 15, 2023

Back door of RV came opened while driving down the road. The door is always locked (dead bolt included) and the entry-assist arm folded over the door during travel. Upon parking for the evening, it was noted that the back door of the RV had popped open during travel.

NHTSA ID

11620693

Incident

Sep 18, 2024

Excess frame flex. Contacted Grand Design, they scheduled an inspection and then preformed followup repairs. New bracing and support were added by Grand Design.

NHTSA ID

11605321

Incident

Jun 10, 2024

My grand design had the have frame flex fixed twice and it’s still not fixed correctly. None of the aluminum behind the cap was fixed as grand design didn’t want to fix it and lippert would on touch the steal frame.

NHTSA ID

11591176

Incident

Jan 20, 2022

We noticed our pin box on our GD started moving when we hitch up. The wall inside the bedroom is showing wear from movement, the trim around the upper deck came apart multiple times, the flooring inside the bedroom had a hole in it from the bed gouging into it. When hitching up the wall is bulging out on driver side just off of the slide corner. Our slide stopped working and there are Gibs inside the wall of the slide that had sheared off rivets.

NHTSA ID

11577689

Incident

Mar 15, 2024

I have had front flex on my grand design repaired twice already and it’s still has issues. They didn’t weld any of the aluminum back together they would only do the frame, my bedroom walls and cabinets wouldnt get fixed either because that’s cosmetic.

NHTSA ID

11569768

Incident

Feb 15, 2022

The front area where the pin box connects to the truck has multiple welds are breaking on the structural frame causing these trailers over flex while driving down road. There has been multiple cases of the front deflection being out of spec on multiple trailer. With these welds broken it can cause the trailer to separate where the truck would hook up to the trailer and if the concern is not addressed.

NHTSA ID

11457245

Incident

Feb 22, 2022

The contact owns a 2020 Grand Design Recreational Momentum. The contact stated that the floor was started buckling and there were bubbles on the flooring of the trailer. The contact stated that one of the bubble was near the front bedroom towards the bathroom, and the other bubble was towards the hallway. The contact took the vehicle to the local dealer however, the mechanic was unable to identify the cause of the failure however, the mechanic was willing to fix the esthetics by sanding the floors and replacing the linoleum. The trailer was repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 1,000.

NHTSA ID

11420475

Incident

May 1, 2020

Mileage

1,000 mi