Flex Air pinbox

[Tom Traveler]

I am considering the purchase of a Curt (Trailair?) Flex Air pinbox to replace our Morryde rubber pinbox. The Morryde does nothing to cushion the up/down jarring of bridge transitions. There is a bridge transition just north of downtown Salt Lake on I-15, going north, that I thought was going to tear the hitch out of the truck bed.

For anyone that has the Flex Air pinbox, can you estimate the amount that the pinbox plate depresses (or sinks) when you lower the RV onto the hitch after hooking up. The Flex Air plate is about 2" lower than the Morryde plate in the unloaded position. I'm trying to find out the height difference in the loaded position. I know that can vary with the air pressure in the pinbox airbag so I will be pulling an 18,000 RV for reference.

Thanks.

[LMagelitz]

I am considering the purchase of a Curt (Trailair?) Flex Air pinbox to replace our Morryde rubber pinbox. The Morryde does nothing to cushion the up/down jarring of bridge transitions. There is a bridge transition just north of downtown Salt Lake on I-15, going north, that I thought was going to tear the hitch out of the truck bed.

For anyone that has the Flex Air pinbox, can you estimate the amount that the pinbox plate depresses (or sinks) when you lower the RV onto the hitch after hooking up. The Flex Air plate is about 2" lower than the Morryde plate in the unloaded position. I'm trying to find out the height difference in the loaded position. I know that can vary with the air pressure in the pinbox airbag so I will be pulling an 18,000 RV for reference.

Thanks.

Have you thought about an air ride hitch for the up-down shock, and keeping the Morryde pin box for the front-back motion?

[Tom Traveler]

Have you thought about an air ride hitch for the up-down shock, and keeping the Morryde pin box for the front-back motion?

I'm not familiar with that hitch. If it is what I think it is, I need a slider hitch in my short bed truck and I don't see how it would work. Do you have a link or a picture to help me see what you are referring to?

Thanks.

[JKJavelin]

Not exactly apples to apples, but I switched to the AirRide pinbox (same thing but without the extra pivoting plate) 4 years ago, and IIRC it raised the height something like 1.5 inches. Now, I don't inflate the bladder all the way to the maximum line, but maybe 2/3 of the way. My pin weight is about 2800 lbs and I inflate it usually 60-65 psi.
Great pinbox.
JK

[Tom Traveler]

Not exactly apples to apples, but I switched to the AirRide pinbox (same thing but without the extra pivoting plate) 4 years ago, and IIRC it raised the height something like 1.5 inches. Now, I don't inflate the bladder all the way to the maximum line, but maybe 2/3 of the way. My pin weight is about 2800 lbs and I inflate it usually 60-65 psi.
Great pinbox.
JK

I’m figuring about the same as you, 1.5”, for height difference as compared to the Morryde, based upon the dimensions. I could move it up one row of holes in the wing set to get 2” lower if I need to. The Flex Air is also about 80 lbs heavier than the Morryde. I have about 700 lbs of payload left with the RV loaded so that’s not a problem.

I really want to do something to reduce up-down road shock. I was considering the Gen-Y but I like the Flex Air’s design better and it is adjustable.

The perfect pinbox would be a combination of the Air Ride’s air bag and shock absorber with the Morryde’s rubber back and forth plate

[LMagelitz]

I'm not familiar with that hitch. If it is what I think it is, I need a slider hitch in my short bed truck and I don't see how it would work. Do you have a link or a picture to help me see what you are referring to?

Thanks.

Sorry, I didn’t realize you have a short bed. I have a Hensley BD5 hitch, but none of the air hitches are sliders. I did use it in a short bed Chevy for a trip to South Dakota, but watched it closely when maneuvering. I do highly recommend it, it really relieves the shock to the trailer frame. Probably the same can be accomplished with an air ride pin box, but will give up the front-back cushioning.

[Tom Traveler]

Sorry, I didn’t realize you have a short bed. I have a Hensley BD5 hitch, but none of the air hitches are sliders. I did use it in a short bed Chevy for a trip to South Dakota, but watched it closely when maneuvering. I do highly recommend it, it really relieves the shock to the trailer frame. Probably the same can be accomplished with an air ride pin box, but will give up the front-back cushioning.

Thanks for the picture. That looks like a nice hitch if you don't need a slider.

Lippert claims the rubber padded rotating kingpin plate takes up some front to back motion. With the rotation point of the hitch plate and the rotation of the kingpin plate being about 5 inches apart, I can see how it will take up some front to back motion as the entire hitched assembly will rotate around a common center between the two pivot points. That rocking back and forth will translate into some up and down motion that should be absorbed by the airbag and shock so hopefully it will be the best of both. I think the up and down shock is harder on the frames of these heavier trailers than the back and forth anyway, so I'm thinking it's a worthwhile tradeoff from the front to back capability of the Morryde.

[WhittleBurner]

Thanks for the picture. That looks like a nice hitch if you don't need a slider.

Lippert claims the rubber padded rotating kingpin plate takes up some front to back motion. With the rotation point of the hitch plate and the rotation of the kingpin plate being about 5 inches apart, I can see how it will take up some front to back motion as the entire hitched assembly will rotate around a common center between the two pivot points. That rocking back and forth will translate into some up and down motion that should be absorbed by the airbag and shock so hopefully it will be the best of both. I think the up and down shock is harder on the frames of these heavier trailers than the back and forth anyway, so I'm thinking it's a worthwhile tradeoff from the front to back capability of the Morryde.

Air Safe does make a sliding air hitch and have for some time. We have had a Air Safe hitch since 2015 and still love it. When we bought ours they had the sliders available then.