Fifth Wheel Hitch Heigth

For the truck rails: 6 inches is minimum; most want 8 inches. That is the critical measurement.

At 4" when you get in any rough or hilly ground there will be contact.

Is your trailer level? Four inches is really not enough, you may have to raise the hitch making it a bit nose high which is not ideal.

I think what you are saying is that your top of hitch is 4"s below the bed rails. I would guess that most are 2-3 inches lower than rails. Do you have the FW, to hook it up, see if you need to raise hitch higher? The end result should have your FWs under side at least 6"s higher than bed rails. All FW pinboxes are not shaped the same, and can be raised lowered as needed. You'll have to hook er up, then decide best option for your set up.

Jerry

6” between the truck bed rails and the underside of the 5er overhang is what is important. That’s where possibly hitting may occur. Hitch height has to be adjusted to get that clearance but is not a standard height.

MFL - you've answered my question. Thank you. I did not know that pin boxes could be adjusted. My 5th wheel hitch is 17" max and my truck bed rails are 21". I'm not getting the trailer until November so I'll have to wait to get the trailer in order to figure things out.

Pin boxes can be adjusted, but they are heavy. Better have two guys to do the adjusting you and a buddy. Or better yet make the dealer do the adjusting, it has to be set before you hook up anyway. And don't let them stop until they have it just right.

agesilaus wrote:
Pin boxes can be adjusted, but they are heavy. Better have two guys to do the adjusting you and a buddy. Or better yet make the dealer do the adjusting, it has to be set before you hook up anyway. And don't let them stop until they have it just right.

While a pin box can easily be adjusted by single person using your tailgate and landing gear.
I would make the dealer do it, getting the nuts and bolts loose usually requires an impact wrench.

I had 5 inches with first truck pulled out of a parking area up a small incline turning left. I didn't see the damage until I stop for gas. Small dint in the top of box

MFL wrote:
I think what you are saying is that your top of hitch is 4"s below the bed rails. I would guess that most are 2-3 inches lower than rails. Do you have the FW, to hook it up, see if you need to raise hitch higher? The end result should have your FWs under side at least 6"s higher than bed rails. All FW pinboxes are not shaped the same, and can be raised lowered as needed. You'll have to hook er up, then decide best option for your set up.

Jerry

Reading is fundamental!!! You beat me to it!