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4x4Fun
06-05-2019, 08:44 AM
I’m new to the fifth wheel world. I have a 2015 Ford F-350 XL 4x4 SRW with all available towing and camper packages. I bought it used. It is lifted quite a bit, has a 100 gallon bed tank plumbed to the main, and a toolbox behind that. I just bought a 2009 Keystone Raptor 3602RL as a functioning DIY project. I’m getting the rig delivered to my house since I don’t even have a hitch yet, and there seems to be LOTS of options there! I’m sure the trailer needs to be level when in tow, but how level is level enough? I’m worried my truck is lifted too much. I’ve heard you can flip the axles on the trailer to get some more height at the hitch. Then I’m concerned about clearance on the toolbox when turning. Any advice would be appreciated as I don’t even know what I don’t know. Thanks!

wingnut60
06-05-2019, 09:06 PM
Welcome to the forum!

Lifted trucks are always problematic getting the towed unit to sit level. Logically, you can only lower the truck or raise the trailer. Flipping the axles is most common way to lift the trailer, but can also consider a spacer tubing between the frame and the spring mounts. If you were to put the spacer tubing in, any competent spring/axle shop can do this, and it would be a great time to reinforce the spring mounts.
In addition, depending on the quality of the lift install, it in itself may cause towing problems, guess that has to wait on getting hitched up.

Notanlines
06-06-2019, 08:02 AM
4x4 fun, what is the cargo capacity of that F350 beast you’re going to be towing with? From the sticker on the door post....

wingnut60
06-07-2019, 10:22 PM
Along with that question from Notanlines--what is the GVWR of the trailer you bought?

4x4Fun
06-08-2019, 04:32 AM
Why would the spring mounts need to be reinforced? Just want to learn some I can test service providers’ credibility when I talk to them.

4x4Fun
06-08-2019, 05:18 AM
GVWR=11500. Rear GAWR=7000. Brochure says max fifth wheel trailer weight is 15900.

4x4Fun
06-08-2019, 05:28 AM
Brochure says trailer is 13000 and 3500 max cargo.

Notanlines
06-08-2019, 09:51 AM
4 x 4, this won't be what you want to hear, but you don't have near enough truck. Just the pin weight, 5th wheel hitch and your aftermarket tank put you a good 1000 pounds out of the envelope. Probably more than that when you're ready to go. And you're going to tow with a lifted truck? Not even close to a good idea. I'm just sayin'...

wingnut60
06-08-2019, 10:00 AM
Anytime you raise the center of gravity, you put more stress on the suspension components in turns, expecially sharp backing turns. Internet has many mentions of factory spring mounts failing--most towables are built to minimum specs needed, with little margin for increase in stress, that is why I suggest if adding height, you reinforce/rebuild the spring hangers.
Also, if the GVWR of the trailer at 13000, you could have as much as 2600lbs of pin weight. With a 100 gals of fuel in the tank, the trailer loaded for camping, you will probably be over the RAWR and over the rear tire capacity--tho, with a lift, the tires MAY have more carrying capacity than normal. Check it all out--towing with a lifted truck can be hazardous to your health and that of others....

k5ate
06-12-2019, 12:36 PM
GVWR=11500. Rear GAWR=7000. Brochure says max fifth wheel trailer weight is 15900.

The NADA specs (https://www.rvusa.com/rv-guide/2009-keystone-raptor-toy-hauler-floorplan-3602rl-tr6716) show that to be closer to a 16,500 gvwr with a 2,870 pin weight. That pin weight will be dry, so loaded you might be significantly higher. Toy Haulers often are pin heavy when dry so that, when you load your toys in the garage the pin weight comes "up to normal". So it is theoretically possible that you may be anywhere from 2,500 to 3,500 pin weight. However, fivers often get up to about 25% of weight on the pin so you could see just over four thousand pounds on the pin. You won't know till you load it up and CAT scale it. You can move weight between the garage and front storage to a degree of course, but you've only got so much to play with. It depends on how the unit is designed if it will allow much room there.

As has been noted, with a SRW truck you're probably going to be over capacity. Figure a thousand pounds of fuel and fuel tank, plus gear. You're probably at maybe 1,500 pounds left for pin weight, but you'll have to CAT scale it to be sure. That's not including your toolbox of course. You can easily get eight hundred pounds in a toolbox and tools. I'd take it to a CAT scale to see where you are now.

Opinions abound on the advisability of upgrading your truck to haul over spec. The tires are the most obvious weak point. At a 7,000 pound rear GAWR your factory tires are probably in the neighborhood of 3,750 max. With that fiver you're going to be well over on the chassis as well as way over on the tires.

There are options, all of which are sub-optimal, but they are options:
--You could go to 19.5" wheels and tires. You can get 8 hole 19.5" rims and 19.5" tires will allow you to get significantly more capacity, but your choice in tires is limited.
--You could convert it to duals. Again, your choice of tires is limited due to spacing but lots of guys are fine with the tires hanging out in the breeze. I've seen guys put different sizes on the front and rear. As long as the diameter is the same (for 4x4 work) you might be ok.
--You could forego filling your aux tank and gain about eight hundred pounds of payload back.

Regarding hitch and towing level... If you aren't towing level you're overloading your rear axle and tires. The primary limiting factor is clearance between the bed rails and underside of the fiver. You need at least five or six inches of clearance or you're going to put fiberglass to metal and neither will come out well. One option would be to go to a flatbed. You get rid of the clearance problem and can set your hitch and kingpin to lower down and flatten out your fiver. However, most flatbeds are heavier than the bed than replace.

The bottom line is, as was said, you don't have enough truck or you've got too much fiver. You do see guys out on the road pulling with a lifted and/or SRW truck all squatted down with the nose of the fiver pointed up high. Often they pass me like I'm going in reverse.

You make your choices you take your chances.

Be safe!

Kate

wingnut60
06-18-2019, 11:02 AM
Kate, well said.