Lift Solutions for Trailer for Towing with New Truck that Sits Taller

Question:

I recently traded my 2016 F350 for a 2021 F450. The new trunk is about 3inch taller and now the 5th wheel pin box comes in contact with my bed side rails. Will the 20k reese goose box clear my bed rails?

asked by: Harold W

Expert Reply:

The Reese Goose Box part # RP85FR is not going to give you a significantly different height from the pin box you have now so just it alone would not give you the clearance you'd need. Best option would be to lift the suspension of the trailer.

You can do this by moving the axles from being above the leaf springs to below the leaf springs.

The diameter of your trailer axle will determine the size of the parts that you will need to order. If your axle is 3 inches diameter, the Dexter Trailer Springs Over-Under Conversion Kit, # K71-385-00, would be a great choice and if your axle is 2-3/8 inch diameter you could use the Over-Under Kit, # K71-384-00. These kits can be installed without welding but the manufacturer strongly recommends having the new spring seat tacked in place on the other side of the trailer axle.

Some refer to this process as "flipping the axles," but since axle has a slight bow to it you can't just flip them and reinstall them under the springs using the same spring seats. You have to install new spring seats on the opposite side of the axle so that it can be moved below the spring.

As long as your trailer matches the following three criteria an over-under kit would work well.

The trailer leaf spring stack is currently mounted under the axles
The trailer uses double-eye springs
And the trailer has 2-3/8 inch or 3 inch diameter round axles

We also have 2-1/4 inch lifts like the # RR23QX.