5th wheel with frame flex issues. Compartment doors and entry/exit doors open while traveling down the road. The underlying issue is frame flex.
2021 Grand Design Momentum suspension complaints
Page 2 of 2: complaints 11 to 19 of 19, newest first, as owners wrote them.
Our frame is showing signs of excessive flex, when we hook up our trailer to the tow vehicle.
We are victims of frame failure. First sign was a creaky floor in the bedroom. Screws worked their way out of the wood flooring and pushed up underneath the linoleum. The movement of the nose cap pushed screws out of the trim and seal piece on the underside of the front cap. We reseated screws, upgraded screws, resealed this at least 5 times and now use gorilla tape to avoid water intrusion. The underbelly has fallen down while traveling so we had to reinforce this ourselves. Our driver side bay door will fly open when traveling. It locks but the locks will not hold it closed when the rig starts to flex. We now gorilla tape the door every time we travel to avoid objects flying out of our bay into traffic. The partition between the wet bay and the storage bay has bent. Our front driver side jack is not straight, it points outward. There is rubbing of the shelving and trim in the bedroom. The board that has the slide rollers under the main bed has failed. We have pinched decals on the exterior of the nose cap. The pin box sinks up into nose cap when hitched up. We have a toy hauler however we do not haul any vehicles or toys in our rig. We have had to replace both back leaf springs due to them failing. The main lighting panel has been damaged in transit so that the exterior accent lights will no longer turn off. This is an electrical hazard as well as an annoyance to anyone that camps near us. The roof seal that attaches the roof membrane to the front cap is elevated and not flush. When traveling from TX to Indiana for our frame failure appointment, the roof membrane completely shredded and fell back over the air conditioner. We had to gorilla tape the remaining roof to make it the rest of the way. Grand Design is not issuing a recall yet. Our rig is dangerous for us and anyone on the road with us. Our rig is in the shop right now and we have the highest hopes that it is properly fixed, and we do not have to return like so many others are.
There are hairline cracks in the frame / Axle hanger(s), throughout the entire inside floor there are drops / gaps when a level is put down of a minimum of 1/8" - showing symptoms of frame flex / failure. On the road, the trailer produces excessive sway, bounce, and movement at speeds of 45 mph and above to the point where control has almost been lost on the roadway. It has been towed and tested with 3 different vehicles (2019 F250 Diesel, 2022 F450 Dually Diesel, and 2023 F250 Gas). documentation, video proof, Multiple witnesses, and different drivers all with over 7+ Years up to 30+ years' experience have tested this and have come up with the same results. Upgrades were made to both tow vehicle(s), Hitch(es), and trailer as suggested by Grand Design RV. Grand Design has stated after investigation that the axles on this unit were installed 5" out of the normal manufacturing of a Momentum 31G and there is a 1/2" difference between the driver's side front axle hanger and rear passenger side axle hanger. Trailer has been weighed multiple times with various loading procedures to make sure everything was evenly distributed side to side and front to rear. The trailer has not been overloaded yet the leaf springs were flat before upgraded to heavier weights. Tires have shown uneven wear patterns. Hitches have been set up in various positions per manufactures requests without any success. Grand Design has not taken responsibility nor attempted to fix the issues with the unit even with the proof submitted to them. Instead, they have been combative, dismissive, and try to bully their way out of their responsibilities. I've invested my own funds over the course of 3 years to attempt at rectifying the issue with no success. My family will not even travel in the same vehicle as me because they fear for their safety as I do as well as the safety of everyone on the roadway. This, however, does not concern Grand Design as they've unprofessionally stated to me consistently.
Frame flexing issues. Storage compartment doors opening while towing and loosing belongings.
In february 2023 we noticed several internal (sawdust, exposed finish nails, floor noises, broken trim, pinched wall coverings) and external (multiple locked doors opening in transit)signs that our RV frame was experiencing excessive flexing, more than what is expected and necessary for a nearly 42' metal vehicle frame. The frame has since failed, the suspension is underrated for the weight of the vehicle. The manufacturers UVW and GVWR sticker knowingly contained incorrect OEM information with proof from a CAT scale leading to me as the owner believing the vehicle could have been loaded with more OEM item weight from the manufacturer than what was accounted for and annotated. Despite understanding the allowable weights and keeping this RV well under the advertised GVWR, the 6 separate leafsprings of the suspension are all flattened. The upper deck frame failed under normal on-road (and very little) use. A 2024 TSB was issued on my RV for "upper deck flex". .5" of movement at the pin box was the "within limits" passing grade. My unloaded and empty RV's measurement taken by an authorized service center by the manufacturer in keeping with the TSB, measured 1.5" of flex at the pin box. This failure was so great it led to the manufacturer instructing the Service center to not move it or release it to me out of safety concerns. It has been at the service center since 4/10/2024 ti present without any instruction or communication from the manufacturer on how to proceed either under warranty or otherwise.
Frame failure causing the vehicle to be unsafe to tow given the failure is in the PIN area. If the PIN box fails that could cause a catastrophic accident resulting in great harm or death to the driving public. Grand Design has failed to take full ownership of this issue with 100's of their large 5th wheel. On inspection welds are weak or missing leading to these RV's becoming unsafe to tow down the road. While GD has approved some work to remediate the broken welds, it's minimum effort and not a full fix. It will still be unsafe to tow with root cause in their upper deck walls not being addressed.
This is in addition to safety report #11540112. While further inspecting the trailer, the right rear shackle bolt was also found to be broken in half. The spring was still on, but it was probably working its way out, which would have cause the same failure as the left side, in the original report.
Left rear wet bolt sheared mid-bolt at the hole where the grease comes out to grease the sleeve in the spring eye. Spring was sliding side to side, causing the shackle hanger to bend and the spring to detach from the shackle. I have Summo springs on the trailer, and the one on the left rear took the weight of the trailer, and may have prevented further issue's. This occurred on the freeway at approximately 65 mph. Safety concern would be uncontrolled axle due to the spring holding the axle not being attached to the frame, and possible uncontrolled swaying.
VIN decoder
See the problems and recalls for an exact car
Buying a used 2021 Grand Design Momentum?
Check the exact car before you pay: accidents, salvage or flood titles, odometer readings and previous owners.
Check its history