Fifth Wheel Pin Box?

[Bunyan]

I purchased a 99 Jayco Designer 3230 33' 11500 GVW 5th wheel and need to buy a pin box for more room in between the tool box and for better ride. The rv only has the square pin box under the front. I do not know what brand the trailer frame is. Bought the trailer Saturday and will pick it up this Friday using my father-in-laws truck. Thanks, Bunyan

 

[RustyJC]

That vintage of Jayco should still have the Leland Engineering frame. Note that this is NOT Lippert (many people confuse the two).



You may want to check with Jayco as my last Designer 5th wheel (a 2000 3610RLTS) had a vertical pinbox, and offset pin boxes were not an option nor were they allowed for that model due to additional frame stresses imposed by the offset.



Rusty

 

[jelag]

I've seen 2 5th wheel trailers where the owner changed the pin box to allow for more room between the trailer and the bed. . in each case both of the guys have had troubles with the added leverage placed on the frame of the trailer, and with higher mileage failure or bending of the frame where the pin box is installed...

I chose to modify my B&W turnover ball and companion hitch by building an adapter and moving the companion hitch back 12"... . it now sits behind the rear axle... I have a 15K lb trailer and tow with a 3500 dually, it has air bags, and we inflate the air bags to level the truck... once the truck sits level we've no other changes... I'm guessing we now have close to 50K miles on this truck/trailer combination...

 

[Cummins12V98]

I've seen 2 5th wheel trailers where the owner changed the pin box to allow for more room between the trailer and the bed. . in each case both of the guys have had troubles with the added leverage placed on the frame of the trailer, and with higher mileage failure or bending of the frame where the pin box is installed...

I chose to modify my B&W turnover ball and companion hitch by building an adapter and moving the companion hitch back 12"... . it now sits behind the rear axle... I have a 15K lb trailer and tow with a 3500 dually, it has air bags, and we inflate the air bags to level the truck... once the truck sits level we've no other changes... I'm guessing we now have close to 50K miles on this truck/trailer combination...

So what you are saying is you are taking a lot of weight off your front tires. With my B&W full forward I am only adding 100# to the front axle with 4,500# pin weight. You have defeated the purpose of a 5th wheel set up. Industry standard is 2" ahead of center line of rear axle. If you did not have a dually you probably would have bit it by now. Just sayin!

 

[jelag]

I made the change on my unit to have the ability to put a box behind the cab on my truck... my truck has a flat bed on it and it allows me the extra storage for travel to and from our winter home. . in addition I installed an air bag in the pin box to absorb some of the shock. . we used a laser and formed a new pin box with an airbag and shock to take some of the bounce out of the trailer...

My truck also runs 19. 5" tires and wheels... In addition we upgraded the tires on the trailer... I agree with you... we've moved the center point of the load to behind the axle... not what your supposed to do... the point in my first post was to share that if you alter the pin box to move the trailer back you take the chance of damage to the trailer frame from the offset of the load that the frame might not be designed to handle...

Hope this helps clarify my thoughts. .

 

[Cummins12V98]

I made the change on my unit to have the ability to put a box behind the cab on my truck... my truck has a flat bed on it and it allows me the extra storage for travel to and from our winter home. . in addition I installed an air bag in the pin box to absorb some of the shock. . we used a laser and formed a new pin box with an airbag and shock to take some of the bounce out of the trailer...

My truck also runs 19. 5" tires and wheels... In addition we upgraded the tires on the trailer... I agree with you... we've moved the center point of the load to behind the axle... not what your supposed to do... the point in my first post was to share that if you alter the pin box to move the trailer back you take the chance of damage to the trailer frame from the offset of the load that the frame might not be designed to handle...

Hope this helps clarify my thoughts. .

Thanks for the reply.

Have you ever weighed the front axle with and without the rv?

 

[Bunyan]

I've seen 2 5th wheel trailers where the owner changed the pin box to allow for more room between the trailer and the bed. . in each case both of the guys have had troubles with the added leverage placed on the frame of the trailer, and with higher mileage failure or bending of the frame where the pin box is installed...

I chose to modify my B&W turnover ball and companion hitch by building an adapter and moving the companion hitch back 12"... . it now sits behind the rear axle... I have a 15K lb trailer and tow with a 3500 dually, it has air bags, and we inflate the air bags to level the truck... once the truck sits level we've no other changes... I'm guessing we now have close to 50K miles on this truck/trailer combination...

I understand about undesirable forces on the trailer frame. At this time, I'm waiting for a response from the manufacture for proper details. I was asking the guys which box they prefer. If the manufacture gives the ok for adding the extended pin box, I'll need one for installation. There are many things a person can alter in order to meet there needs. I will not put the lives of my family or fellow man in danger to accomplish dangerous driving or towing conditions to satisfy my personal needs.

 

[RustyJC]

If you get the OK, I'm very happy with the Demco Glide Ride extended pin box on our rig. It eliminates probably 80% to 90% of the fore-aft "chucking" and surging you can experience with a solid pin box.



Rusty

 

[EricBu12]

Get the super 5th Airborne sidewinder pinbox. . do a search. There are 3 types. . one with just the sidewinder turret, one with just the air ride box. . and one with a combination. . this is what I have. . I have a 36' 5th wheel toyhauler and it has worked wonderful. Makes a smooth ride and is originally made for 3/4ton sb to make a 90deg turn. So this will help you with your toolbox... this is expensive but worth it.

 

[Bunyan]

Thanks for the help gents... Bunyan