7k axles vs 8k axles

[DHM34]

New to Grand Design and this forum. Just curious if I'm missing something on figuring weight and axles. I'm buying a 2023 380FLR. GVWR is 16,800lbs. Unloaded weight is 14,866. Pin weight is 3052. If I understand correctly, that's without any additional weight including generator, washer/dryer and third AC unit. This unit came from the factory with all three of these options. It does have the upgraded H rated tires and the 17.5" wheels. But it only has the 7k axles. The way I see it I can only add an additional 900 to 1000 pounds of contents. Is this right? Why the heck would Grand Design even ship a unit where it will basically need a $5000 upgrade for bigger axles before it even leaves the dealer lot? So frustrating! Thanks for any advice.

[TucsonJim]

That pin weight of 3052 is for an empty fifth wheel. Most of the rigs run about 22 to 25% of the weight on the pin. If you loaded the RV to the maximum GVWR of 16,800 pounds, and had 22% on the pin, you'd have a pin weight of 3,696#, and 13,104# on the axles with an axle capacity of 14,000#. This would be within the capacity of the axles as long as the weight was properly distributed to not exceed either one of the 7,000 pound axles.

If you have even more weight positioned at the front of the RV, you'll have less on the axles. For example, you mention a generator. Most of that weight will fall on the pin. But then since the washer/dryer go behind the rear axle, the opposite is true.

Jim

[Cate&Rob]

The paperwork that comes with your new trailer should include a sheet with the exact weights of your trailer as it came off the assembly line. If this information is missing, contact Grand Design Customer Service with your VIN and they will send this to you. This will give you an accurate starting point.

Rob

[Skilletface]

New to Grand Design and this forum. Just curious if I'm missing something on figuring weight and axles. I'm buying a 2023 380FLR. GVWR is 16,800lbs. Unloaded weight is 14,866. Pin weight is 3052. If I understand correctly, that's without any additional weight including generator, washer/dryer and third AC unit. This unit came from the factory with all three of these options. It does have the upgraded H rated tires and the 17.5" wheels. But it only has the 7k axles. The way I see it I can only add an additional 900 to 1000 pounds of contents. Is this right? Why the heck would Grand Design even ship a unit where it will basically need a $5000 upgrade for bigger axles before it even leaves the dealer lot? So frustrating! Thanks for any advice.

With all of those upgraded options it does reduce the amount of items you can bring along and you are way ahead of some figuring this out. That stated, keep the fresh water at minimum ,gray and black tanks empty when possible, tools you may wish to carry on the Tow Vehicle. Kitchen equipment be thoughtful, toaster oven instead of a toaster not both, are you really going to use that crock pot? Clothing , only pack for that trip.
As for parking, consider going for pull through sites as to reduce the binding effect to the rigs suspension. Most of the federal, state and county run parks where established when a 25 footer was considered a big camper.
Grand Design is still one of the better engineered & built RV's and will provide what the customer wants. Many of us actually use our rigs continuously and that is where the after market for suspension upgrades enters. I'm not convinced RV's are built to be used every month just look around on the storage lots.
If you are going to use your rig more than most then you'll need to budget for suspension upgrades, it is the nature of the industry and not much different than any other nice to have.

[d2reid]

How you are using your 5th wheel will determine if you need an axle upgrade.. I have paid for heavier suspension on both the 5th wheels I have owned. In both cases it was changing from drum to disk brakes that prompted the start of the upgrade. Then once into it I went ahead and replaced other compoments as well. The main reason for the change is the number of miles I travel on Americas most hated highways. Huge potholes that eat weak suspension. I am a roving full timer.