5th Wheel Purchase

[Chris and Cheryl Hageman]

Hi
We just purchased a 2014 Rushmore Washington Model. We purchased it in SD and brought it to our home state of Texas, and on the road, we seem to experience some chucking over bumpy bridges. We are pulling with a 2016 GMC 2500. Do we need to put air bags on the suspension of our truck, or does the trail air pin need to be replaced. Also we clipped our bed of the truck with the pin while making a sharp curve, and our RV dealership here has adjusted the pin to raise it, so should that correct it?
We would appreciate any other tips, as we haven't taken it out on its maiden camping voyage yet. I just learned about side to side leveling before using the auto levelers. SO MUCH TO LEARN!!

[Dayle1]

That unit has a dry pin weight of about 2900 lbs which is a lot for a 2500HD. Your rear axle GAWR is probably 6084 lbs which is determined by the tire rating. You didn't state what model you have, but an unloaded truck will have an empty weight right at 3000 lbs on the rear axle. Add the weight of the hitch, a percentage of all other cargo/passengers in the truck and you are over the 6084 lb limit. Finally all the cargo, etc you add to that Rushmore will increase the pin weight even more, somewhere between 25% and 40% of the additional weight will be on the pin. So, add 2000 lbs in the Rushmore and you are likely 800 lbs overloaded.

I strongly suggest you take the unit to a weight station and find out exactly how much weight is on the rear tires of the truck. Also, check the tire load capacity, if it is 3042 lbs per tire and you are over that number, then you do have a serious problem. Legally, you cannot change the rear axle rating, but for safety and being legal per DPS, you should upgrade the tires to those used on the 3500 which are rated for 3525 lbs. It is also possible that you already have the higher rated tires on your truck depending on options.

With the weight you are carrying, air bags will level your truck and provide a smoother ride. Legally, they do not increase your load capacity, but technically they do help with load capacity. Basically, you could replace the 2500HD leaf springs with heavier ones on the 3500 or you could add air bags, while air bags are a cheaper solution. I used them on my old 2500HD, don't need them on the 3500, but my Cruiser has a pin weight that is 1000 lbs less than the Rushmore.

Here in Texas, you can register your truck to carry more weight than the truck's GVWR which is likely 10000 lbs. Dealers frequently register the truck at the lowest number possible to keep total purchase costs low, many times even below the manufacturer's rated number. So, you can be in trouble if stopped, so check your registration and change it, you will pay higher fees each year but may avoid trouble. However, you are not legal if you exceed the tire capacity, so again you need to check your actual weight vs. the tire capacity.

In summary, here in Texas you are legal provided the total truck weight does not exceed the REGISTERED weight and no single tire is carrying more weight than the number stamped on the tire.

Finally, the dealer did the right thing by adjusting the pin box. But depending on the specific pin box design, a number of owners gain a little extra clearance by cutting excess metal from the back of the pin box. You will need to do a search for more info and determine if it will work for you. Here is one link with a picture near the bottom of the 1st page.

https://www.rv.net/forum/index.cfm/f...g/1/page/1.cfm

[Lloyd]

Originally Posted by Dayle1

But depending on the specific pin box design, a number of owners gain a little extra clearance by cutting excess metal from the back of the pin box. You will need to do a search for more info and determine if it will work for you.

Larry, can you elaborate on just where and how much is being cut off the pin box?
Can we get a picture?

[Dayle1]

Originally Posted by Lloyd

Larry, can you elaborate on just where and how much is being cut off the pin box?
Can we get a picture?

Done, I edited my post, check out the link.

[Lloyd]

Originally Posted by Dayle1

Done, I edited my post, check out the link.

Interesting. Thanks for the link.

Chris and Cheryl welcome aboard. Congrats on the new rig.

[Dayle1]

Originally Posted by Lloyd

Interesting. Thanks for the link.
.

In many cases, the side plates of the pin box extend further back than the bottom plate, so notching them as shown has no impact on the strength of it, but helps with clearance.

[WoodcarvingGypsy]

Chris, you indicated that you have a TrailAir pinbox. If memory serves me correctly, you need to have the bladder pumped to the point that the arrowheads points are visible (at the edge of the shock sleeve). On our Seville, that's at about 85 lbs or so.

Also, what kind of hitch do you have? We had to raise our SuperGlide about 3 inches (Pullrite makes a kit) to get additional clearance.

I've gotten into the bed cap rails when the TrailAir was low.

[Chris and Cheryl Hageman]

Thank You so much for the reply. We had a BW hitch installed, and have the Anderson Hitch inside the box. On the advise of an RV dealer, we just purchased the Lippert Flex air pin box that has the air bags to replace the Lippert roto flex box that is on the fiver now. We bought this from a friend, and that is what he had on it.
The RV dealer said because our fiver will weigh up to 14000# loaded, the flex air we just ordered will help so much

[woodwalker]

When I got my 2015 Denali I only had 5" clearance from my bed rails with my curt Q24 set at its highest setting and the rotoflex pin box at its lowest. I went to the FlexAir Pin Box which now gives me 7" clearance. I contacted the underside of the trailer pulling out of a gas station with only 5" of clearance. I then ran into the problem of the back end of the pin box contacting the rails . I have a pace Edward's Electric tonneau cover which sits up 1" above the bedrail. I trimmed the metal off the rear of the pin box and solved the problem. My trailers pin weight is 4200 lbs and I run 90 psi in the airbag which eliminates the chucking. Air bags on the truck will definitely help smooth the ride as well

[Dayle1]

Originally Posted by Chris and Cheryl Hageman

Thank You so much for the reply. We had a BW hitch installed, and have the Anderson Hitch inside the box. On the advise of an RV dealer, we just purchased the Lippert Flex air pin box that has the air bags to replace the Lippert roto flex box that is on the fiver now. We bought this from a friend, and that is what he had on it.
The RV dealer said because our fiver will weigh up to 14000# loaded, the flex air we just ordered will help so much

You really need to check the truck's tire rating and weigh the rig, primarily the loaded front and rear axles of the truck. Again, you are likely over the tire rating and over the truck's GVWR. Knowing actual numbers will help you decide on additional steps for safe and comfortable travels.