Ways to Even Out Different Heights of Lifted Truck and 5th Wheel Toy Hauler Trailer

Published 01/09/2015

Question:

Hello, I have a 37 ft fifth wheel toy hauler that I tow with my dually. I already have the convertaball adapter to change 5th wheel to goose neck this saved me 2 3/4. I am considering doing a spring over axle swap so my trailer will set more level while coupled to my truck. My truck has a 4.5 in lift in it and the pickup style bed. My other option is to replace the bed altogether with a flatbed that has a recessed goose neck ball below the deck. My camper already sets 12foot 6inch while coupled to my truck, axle swap will make it 13. I do not really want to mess with the geometry of the trailer, it tows great, but I need some leveling I tend to drag occasionally. You guys have always helped me in the past, your thoughts and advice are greatly appreciated. Thanks.

asked by: Rob S

Expert Reply:

A lifted truck usually brings with it some complications for towing purposes. A trailer axle over-under conversion can be a solution to correcting some of the variance in the heights of the tow vehicle and trailer, but this too comes at a high cost: raising your trailer's center of gravity. This higher center of gravity will tend to degrade trailer handling. Depending on the particulars of the trailer, the benefits of getting the trailer level when hitched could be completely voided by the degraded handling from raising its center of gravity.

If you are willing to remove the lift kit then this is your easiest and lowest cost option. If removing the lift is not an option and if you intend to keep this truck and trailer for a while then I urge you to do as you suggested - replace the standard bed with a flat bed and install a recessed gooseneck hitch.

Depending on your current 5th wheel pin box you may be able to replace it with a Reese Goose Box such as # RP85FR. This strategy offers you the ability to completely avoid the need for 5th wheel-to-gooseneck adapters, such as your Convert-A-Ball. All such adapters increase the stresses placed on the trailer's frame. These replacement pin boxes bolt on to your 5th wheel's pin box wings just like your current pin box. These two Goose Box couplers are direct bolt-on replacements for a wide range of OEM pin boxes.

For example, the RP94622-61301 replaces Lippert pin boxes 0115, 1116, and 1716. Goose Box RP94622 replaces Lippert 0719, 1621, 1621HD and also Fabex PB-600 Series pin boxes. If your toy hauler pin box is any of these then you can bolt on a Reese Goose Box and avoid the chucking and jarring commonly introduced by adapters.

Depending on just how much rear-end drag you have you might consider installing some skid wheels (if you do not already have them on your trailer). The link provided will show you all such items, which include weld-on and bolt-on varieties.

expert reply by: Adam R