New truck issue

[Lost]

I purchased a new truck that sits 4" higher than my old one. I maxed out my new hitch but the 5th wheel is grazing the top of my bed when i hit a dip, hole in the road ( not acceptable to me). The 5th wheel king pin hitch looks like I can lower it a notch. question is how heavy is that and can I do it myself ?

[chuckster57]

Which pin box do you have? When I changed mine, I hitched up to the truck and then undid the pin box bolts.

Drove out, put the new pin box on the hitch, backed up and put the bolts back in.

When you torque the bolts/nuts make sure you have UPWARDS pressure on the pin box.

[rhagfo]

When I raised my pin box, I rested the pin on the tailgate of the truck. Then removed all bolts except the back two. I just loosened the back two. Then lowered the trailer until the front holes lined up. I the. Installed the front two and removed the rear tow and raised the trailer until the back holes lined up. The. Reinstalled all bolts and tightened to correct torque.
You would do the reverse. Sounds like you are towing nose high, best to figure how to raise the trailer at the axles.

[Lost]

A couple of days ago I took my 5th wheel to get tires. I had my wife watch as I backed up to see were and what was scrapping the top of my bed as I backed up and turned my 5th wheel around. I have almost 6" of clearance between the top of the bed and the 5th wheel. When I took a hard turn and a one foot drop the hitch rubbed against the truck bed. I re-examined the trailer hitch. I can't lower it without buying a new king pin hitch. So i have to be careful on how I back up. I can't see any issues of normal driving.

[JRTJH]

Originally Posted by Lost

A couple of days ago I took my 5th wheel to get tires. I had my wife watch as I backed up to see were and what was scrapping the top of my bed as I backed up and turned my 5th wheel around. I have almost 6" of clearance between the top of the bed and the 5th wheel. When I took a hard turn and a one foot drop the hitch rubbed against the truck bed. I re-examined the trailer hitch. I can't lower it without buying a new king pin hitch. So i have to be careful on how I back up. I can't see any issues of normal driving.

????? Did you mean to say the bottom of the trailer upper deck rubbed the truck bed ??? Your "hitch" should be stable in the bed and not moving. The "pinbox and kingpin" should be stable on the trailer and not moving, except to rotate in the hitch....

Maybe I'm missing something, but how can the hitch "rub the truck bed" ???

[Lost]

In my driveway I have to cut the trailer to 90 degrees to get it turned around. The picture with the blue tape is where it scrapes. The picture of the bed rail is where it hits.

sorry i can't figure out how to flip the pictures.

[RollaMo]

Posting pictures directly from a mobile device can sometimes cause them to display upside down.
To prevent this, I always save them to my computer and then post them from there.

[JRTJH]

The only problems with contacting the bed side rails that I've heard of in recent years is with the RAM cargo box bed, which encloses the space above the wheelwells inside the truck bed, making the width between the top of the bedrails too narrow for any conventional pinbox to clear in extreme turns. A "wide box truck bed" should have sufficient width for all pinboxes to clear.... But, apparently that's not the case with your rig.

What I think you are encountering isn't a problem with the hitch, rather the pinbox is too long and when you turn sharply, the rear of the pinbox contacts the top rail of the truck bed. But before making that an "absolute conclusion", you need to do some measurements to determine just what's happening.

Does the rear of the pinbox contact the truck bedrails equally on left turns and on right turns? If not, you might have the hitch mounted "too far to one side"... So, measure the distance from the edge of the hitch head plate to the truck bedrail on both sides. Is it equal? If not, you may need to recenter the hitch. When I had a truck with rails for the hitch to mount, I could move the hitch left or right several spaces and pin it "off center". Although that's pretty easy to spot with a quick look, it's possible, so count the holes on each side of the hitch pins in the rails, and measure the distance from each rail end to the truck wheelwell to make sure the rails are properly centered..

If you have the "factory puck system" in your truck, I've never heard of a problem with the fifth wheel pucks being "off center" but anything is possible, so I'd measure from each puck hole to a known reference on the bed to make sure the holes are evenly placed. Probably the easiest and most accurate way to measure them is to measure from the LEFT hole to the RIGHT bedrail and from the RIGHT hole to the LEFT bedrail. That way you're not trying to measure an almost vertical distance.

Then measure the width of the truck bed, from left inside rail to right inside rail, AT THE SAME LOCATION AS THE HITCH PIN SLOT. That will give you the maximum side to side clearance. Then measure from the centerline of the kingpin to the extreme back end of the pinbox (the part that contacts the truck rails). It should be less than 1/2 the measurement of the bedrails, side to side. If it is greater than that bedrail width, then the pinbox is too long for your truck (although that's hard to imagine on a new truck and a newer trailer)...

If the hitch is correctly centered in the truck bed, then hitch the trailer and lower the truck tailgate. Measure the distance from the tailgate to the front of the trailer (horizontally). That measurement is critical for hitching at an "off angle". If the measurement is "too short" then you risk driving the corner of the tailgate into the front cargo door on the trailer...

If you have a sliding hitch, then you'll need to measure to make certain that the hitch is sitting "square in the bed" because if it is not square, when it slides back, it will be closer to one side of the truck than the other and shorten the distance to that bedrail.

I don't think you can raise the hitch and lower the pinbox to get clearance to keep from hitting the siderails. Doing that will "stop the problem when you're level, but if you are backing at an angle AND encounter a side slope, you risk setting the back of the pinbox onto the top of the bedrail. If that happens, the only way out is to stop backing, somehow raise the trailer to lift it off the rail or risk tearing the truck bed apart trying to pull ahead to straighten the rig.... That's not something you want to encounter, so finding the problem and correcting it before you destroy your truck bed rails is the best solution.

It looks like either the hitch is not mounted center (side to side) or the pinbox is too long for your application. Changing to a shorter pinbox WILL cause the cab to front of trailer clearance to be shorter and increase the risk of hitting the truck cab at extreme angles, so a shorter pinbox with the same hitch may not be the "ideal solution"....

First step is critical measurements, not raising the trailer nose.....

[chuckster57]

Originally Posted by Lost

A couple of days ago I took my 5th wheel to get tires. I had my wife watch as I backed up to see were and what was scrapping the top of my bed as I backed up and turned my 5th wheel around. I have almost 6" of clearance between the top of the bed and the 5th wheel. When I took a hard turn and a one foot drop the hitch rubbed against the truck bed. I re-examined the trailer hitch. I can't lower it without buying a new king pin hitch. So i have to be careful on how I back up. I can't see any issues of normal driving.

looking at the first picture, It looks to me like the pin box is mounted at the highest setting and there appears to be another set of bolt holes lower. So you could lower the pin box one hole if that would help. The part that is hitting the bed looks to be the part that is welded to the frame of the tailer.

[bobbecky]

At times, our pin box would just kiss the bed rails. I solved that problem by doing a little trimming. This was only excess metal on the pin box itself, not the frame structure of the trailer.

[hazmat456]

I'm with Bob on this, the offending piece of metal is not structural and could be removed. This is not an issue with height and raising or lowering either the pin or hitch will not solve it. A shorter pin would.

[Kzneft]

A few things I did...
Lowered the pin around 2 or 3 inches. There was another set of holes in order for me to just move it down and insert the same amount of bolts/nuts.
2nd. I purchased 2" spacers and u-bolts to raise my 5th wheeler up 2 more inches on the axles. Much better. The wheels were way to close to the underside of the 5th wheel from the factory anyway.