Replacing Lippert TrailAir Tri-Glide Pin Box with FlexAir Pin Box

Mike&Pam · 02-22-2017, 03:51 PM

Hello All,

I am going to make a switch from the TrailAir Tri-Glide Pin Box to the FlexAir Pin Box. I have seen that others have done the same. I have a couple questions for those of you who have converted from the Tri-Glide to the FlexAir.

1) Did you have to make any adjustments to your king pin box height and/or fifth wheel hitch height? I am assuming that you probably did not have to make any adjustments. Looking at the 2 pin boxes, they both look like they have very similar geometry.

2) I have always been a bit "nose high" with the TrailAir Tri-Glide. I am assuming that it will be the same with the FlexAir pin box also (using the same holes as before). I am thinking about raising the new FlexAir pin box 1 set of holes in order to bring the nose down a bit. I don't want to adjust the fifth wheel hitch height (i.e. lower the fifth wheel hitch) because I don't want the pin box sitting lower in the truck bed and potentially having issues with the pin box rubbing on the truck side rails on sharp turns. I am thinking that it would be best to make the adjustment at the pin box. Anyone have any thoughts on this? I am having the pin box installed at the dealership. Thus it will not be difficult to make these changes.

I have a 2016 Sequoia 38GKS and a 2015 GMC Denali DRW (8ft bed).

Thanks,
Mike Gillum

Ford truck guy · 02-22-2017, 05:06 PM

Good Morning Mike,

I was told that the Flex Air was about 1/2" shorter than the Tri-Glide.. When I replaced mine, I just used the exact same holes and all is fine.

If the dealer is doing the swap , is it possible to leave the truck there with the trailer? This way you can tell them that no matter the hole position, you want the combo to ride LEVEL . . . They will have no excuses..
ps, I think you will really enjoy the ride of the Flex Air .
Joe

Mike&Pam · 02-22-2017, 05:31 PM

Good morning to you too Joe.

When you say 1/2" shorter, do you mean shorter relative to overall height of the pin box or shorter relative to overall length of the pin box?

If you are saying shorter relative to length, I think that that would provide more clearance between the pin box and the truck bed rails on sharp turns. That would be a good thing.

In my very short experience (just over a year), my wife and I have experienced violent vertical chucking (an up and down motion that feels like the RW is going to be yanked out of the truck) and horizontal chucking (a fore and aft motion that jerks the truck fowards and backwards). In our opinion, the vertical chucking is the worst. It can be rather scary. This mostly happens over bridge joints.

Anyway, now that you have the FlexAir, do you think that it improves any of the stuff that I just mentioned?

Thanks,
-Mike

**piper guy** · 02-22-2017, 07:04 PM

Mike - the Flex Air will probably improve the chucking. However, the other question that must be asked is if you have Airbags on the truck.
If not - that should be your next investment. Also put in an onboard compressor with the wireless remote so you can change pressure easily.

Without the airbags, you are very probably running out of suspension travel and what is happening is that the rear axle is bottoming out on the suspension snubber right about the time that all the pinweight of the coach hits it. Something has to react and what you're feeling is the truck "unloading" rather violently. The airbags stop almost all of this by giving you much more suspension travel and the ability to control the stiffness.

Mike&Pam · 02-22-2017, 07:24 PM

Thanks for the info Vaughan.

Does adding air bags void the manufacturer warranty? Also, what kind of investment are you talking about? Is it big bucks to do that?

-Mike Gillum

**piper guy** · 02-22-2017, 07:36 PM

Mike - I have the Airlift 5000 bags and their wireless compressor on my truck. Parts are about $500 for the bags and compressor depending on who you get them from and sales, etc. labor to do the install will vary widely. In my case I mounted the compressor and did all the wiring and th n had the RV hitch dealer do the bag install. Think they charge me $275 if I remember correctly.

In my rig, with the MorRyde pinbox, the Comfort Ride Hitch and the Airbags it has to be REALLY bad before we feel more than a modest head bob jolt. When we first got it, the ride was as you describe and we almost took it back and trad d for a DP !!

Ford truck guy · 02-22-2017, 08:12 PM

Hello Mike,

The 1/2" would be in the height... But to be honest, I saw no difference.

As far as the ride, 100% improvement over the Tri-Glide in my eyes. But even with the Tri-Glide, you should not have all the movement that you are stating.
I had that feeling when I would hit Bridge approaches, it was bad to say the least . . Once I changed over to the Morryde IS , that ALL went away...

On a cheaper note, some upgraded to the Morryde SRE4000 and added the Joy Rider Shock kits, they also are reporting a difference for less money..

5th_Time · 02-22-2017, 10:09 PM

I don't think there are any GMCs here with airbags. Mostly a Ford necessity.

Ford truck guy · 02-22-2017, 10:25 PM

***** On EDIT ******

I believe they called it Bridge Rebound ....

rob_fla · 02-23-2017, 01:12 AM

I do not have air bags on my 2012 GMC 3500 DRW, but my 38FL pin weight is less than most RL models as I only have about 3000 lbs. Pin Weight.

My biggest problem is not enough weight on my GMC Truck to keep the truck on my overload springs, so I got "Bridge Rebound" with my Redwood that I never had with my previous SOB RL layout as it had about 3800 lbs. pin weight and I had very little "Bridge Rebound" with it.

I ordered some aftermarket Spring Shackles for the rear of my truck that lowered my truck about 1 1/2" and put my overload springs closer to the stops. Now my truck stays on the overloads when going over Bridges and rides much better.
Last Summer I had the MoRyde IS and Disc Brakes installed and also had MoRyde remove the Trail Air Tri Glide (since I already had a catastrophic failure of a Tri Glide) and install a MoRyde Pin Box.
Now with the combination of the Lowering Shackles on the Truck, the MoRyde IS and MoRyde Pin Box on my Redwood, I have a very nice ride again.

Now my concern is at some point in the future when I trade my truck for a new one, will I have to start all over again?

shrode · 02-23-2017, 03:07 AM

Quote:

Originally Posted by Mike&Pam

Good morning to you too Joe.

When you say 1/2" shorter, do you mean shorter relative to overall height of the pin box or shorter relative to overall length of the pin box?

If you are saying shorter relative to length, I think that that would provide more clearance between the pin box and the truck bed rails on sharp turns. That would be a good thing.

In my very short experience (just over a year), my wife and I have experienced violent vertical chucking (an up and down motion that feels like the RW is going to be yanked out of the truck) and horizontal chucking (a fore and aft motion that jerks the truck fowards and backwards). In our opinion, the vertical chucking is the worst. It can be rather scary. This mostly happens over bridge joints.

Anyway, now that you have the FlexAir, do you think that it improves any of the stuff that I just mentioned?

Thanks,
-Mike

Mike - Your chucking may be due to a systemic failure mode in the Tri Glide. This has been discussed in the following thread: http://www.redwoodowners.com/forums/...light=trailair. If you have any excessive movement in your Tri Glide lower jaw, you should contact Lippert and try to get them to replace it with a Flex Air. There has been mixed success with this.

Mike&Pam · 02-23-2017, 03:13 PM

Hi Danny,

Lippert would have sent me a lower jaw (under warranty) that was just a metal jaw with no rubber bushing. This would be the equivalent of the TrailAir AirRide (you can find this on their website). The AirRide king pin has the air bag and that is it.

I didn't want that. I wanted the air bag plus the lower jaw with the rubber bushing. Sooooo.... I bit the bullet and went ahead and bought an entirely new king pin box (FlexAir king pin box).

-Mike

shrode · 02-23-2017, 05:39 PM

Quote:

Originally Posted by Mike&Pam

Hi Danny,

Lippert would have sent me a lower jaw (under warranty) that was just a metal jaw with no rubber bushing. This would be the equivalent of the TrailAir AirRide (you can find this on their website). The AirRide king pin has the air bag and that is it.

I didn't want that. I wanted the air bag plus the lower jaw with the rubber bushing. Sooooo.... I bit the bullet and went ahead and bought an entirely new king pin box (FlexAir king pin box).

-Mike

That's pretty much been their response except for a few cases. They could at least offer a discounted price on the Flex Air. Not much of a way to build a customer base. That's why so many have switched to the MORyde.

RWJSIM2003 · 02-24-2017, 12:09 AM

I received confirmation today that my replacement lower jaw has been shipped from Lippert. I asked about a discount for the Flexair and was told there is not discount offered. The replacement jaw is only being sent our as a courtesy. Sounds fishy to me

**piper guy** · 02-24-2017, 05:39 AM

I'm really expecting a nasty lawsuit over this pinbox at some point. I haven't heard of anyone totally losing the coach, ........ yet. Can you imagine the $$$ suit if a coach broke loose on an interstate and took out a few cars and it was found that Lippert knew they had an issue ......

Last years offer from MorRyde at the Rally was just too good to pass up .... and no regrets at all.

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