How I "may" have wrecked the Tri-Glide feature of my Trailair Pinbox

jbeletti

Well-known member
Hi all,

I'm posting this to let people know how I "may" have wrecked by Tri-Glide feature of my Trailair Pinbox - all in an effort to help you prevent the same.

My Setup:
- 2011 Heartland Landmark San Antonio
- Lippert Electronic/Hydraulic Leveling (4 point)
- Trailair Pinbox with Tri-Glide lower jaw

The Symptom:
About 3/4 the way into my last day of travel to the Branson rally this week, the RV began banging against the hitch in the truck when stopping and then tugging back when starting from a stop. Figured it had to be the Tri-Glide as this is the only item in my setup that allows any push-pull motion.

The Failure:
Upon inspection, the lower plate of the Tri-Glide was smashed up against the upper section of the Tri-Glide. That is, there was no gap anymore. The back corners of the plate had also bent downward as if they were trying to wrap around my 5th wheel hitch plate. On the top of the lower plate, on each side were deep grind marks where the upper portion was grinding hard on top of the plate.

Unhitching:
Simply stated - I could not pull the hitch handle, no matter what I tried. Until I dumped the all the air from the air suspension on my truck. First time I ever had to do this to unhitch (out of hundreds of uses).

Further Inspection:
After I got unhitched and leveled out the RV, I inspected the pinbox further. The lower plate of the Tri-Glide had now dropped down to reveal a gap above it where I could look into. I noticed a difference between the left and right sides, inside the Tri-Glide. So something had failed for sure. But why?

One "possible" explanation":
On travel days, we do not unhook the truck. I want to stabilize the RV and level it a bit if possible. My practice has been to lower the front jacks until they take a small amount of pressure off the truck. Then I drop the rear leveling jacks until the touch the ground. From there, I read the lights and the display to determine how out-of-level I may be, then gently tweak the leveling, taking care not to take too much pressure off the hitch. I am never able to fully level the coach as invariably, the terrain will not allow it when connected to the truck.

What I think may have happened, after 9 months of using this method of slightly, manually leveling when needed, is to weaken the internals of the Tri-Glide to the point where the last time it happened, it was the "straw that broke the camel's back". Then, 4 hours into driving, during a movement of the Tri-Glide, it simply failed. Then driving another couple hours with it failed, it really messed itself up by grinding and bending.

Resolution:
Lippert sent me a new Tri-Glide jaw and Terry (can't recall his username), a fellow Heartlander helped me remove the old and install the new. I'd hate to do a Tri-Glide upgrade alone! Be easier to install an assembled Trailair with Tri-Glide than to do a Tri-Glide upgrade - IMHO. The Tri-Glide weighed 118 pounds and had to be "maneuvered" to get out and then back in :)

Conclusion:
So, I share all of this not to only show what an idiot I may be, but to advise others who may also stabilize and slightly level their rigs when attached to the truck, to take great care to make little, to no changes in pressure and geometry to the pinbox/hitch area when doing so.

Pictures:
Below are some pictures taken with my phone during the inspection and repair phase.

Grinding on Plate and Internals Out of Place.jpg Side View of Plate - Grinding and Bent Corner.jpg Lower Plate Bent at Corners.jpg Tri-Glide Removed.jpg Bottom Plate of Air Spring.jpg Keyway on Top of Tri-Glide Section.jpg Used Bolt and Claw Hammer to Remove Pin.jpg Large Diamter and Length Pin.jpg Completed Tri-Glide Installation.jpg

Resources:
I have attached Lippert's Tri-Glide Installation Manual. For those who have the Tri-Glide, pay attention to a couple of things.
  1. Bolt Torque:
    There is a 9/16" hex headed bolt on each side of the Tri-Glide that hold the large diameter long "Pivot Pin" in place at the rear of the jaw. The required torque of these bolts per Lippert is 90 to 110 foot pounds. I also noticed a bit of red Loctite threadlocker on the rearmost threads of these bolts. I see nothing about its use in the manual - but it's probably a good idea. Mine were not very tight and I spoke to Mickey today and he told me he had one that was really backed out!

    The bolts/nuts on the top and bottom of the shock mounts are also 9/16" and require the same 90-110 foot pounds of torque.
  2. Lubrication:
    There are 9 grease zerks on the Tri-Glide. Three each on each side of the Tri-Glide are clearly visible. But there are 3 more that are rather hidden. They are above the lower plate and are accessible from behind the pinbox.
 

Attachments

  • 0170b-tri-glide-pin-box-lower-jaw.pdf
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cookie

Administrator
Staff member
One question, or recommendation. Did you use red Lock Tite on the bolts that hold the pivot pin in place? I had one fall out and was told by Lippert that it should have had red Lock Tite. It does now. In fact they Jerry over there did it for me.

Peace
Dave
 

jbeletti

Well-known member
One question, or recommendation. Did you use red Lock Tite on the bolts that hold the pivot pin in place? I had one fall out and was told by Lippert that it should have had red Lock Tite. It does now. In fact they Jerry over there did it for me.

Peace
Dave

Dave,

I suggest the use of Red Loctite in my post but no, I did not use it. Picking up some today to add it to the bolt threads - then I will torque to specifications.

Jim
 

DW_Gray

Well-known member
Thanks for the info Jim.

Amy and I are having a great time with Dave and Amy at the Wyoming Rally in Hill City, SD.
 

SouthernNights

Past South Carolina Chapter Leader
Thanks for posting this Jim. We very rarely not unhook but this is still good information to have.

Glad you got your rig rolling again.
 

porthole

Retired
Jim - I would have to think that the pin box should be able to carry an equal load, whether it is being pushed down by gravity or thrown upwards by road conditions. And the side to side leveling should be taken up in the hitch head, assuming your saddle moves in 4 directions.

When I had the tri-glide I never hesitated to operate it exactly as you do, jacks down, level side to side etc.
How did the greasable areas look when you took them apart?
 

Ray LeTourneau

Senior Member - Past Moderator
So Jim, had you been lubing all 9 zirks?
I don't know if you read a post of mine a few weeks ago. I had repositioned the trail air within the pin box. I moved it back and up in the box and added a couple degree downward tilt to the trail air. My reason was the lower jaw on the tri glide was not sitting level while hooked up. This was causing the glide to rest on the rearward limit of travel. It also may have been the reason the glide seemed to be "not gliding". Another problem I resolved doing that was to increase the rear pin box clearance with the truxedo frame rails. We're going out next weekend and this will be a good test to see if my calculations were OK.

I hope all works out with your new lower jaw. Trust me, I know what you had to go through to swap it out.;)
 

jnbhobe

Well-known member
My question too Jim, were you greasing all 9 fittings every 1000 miles like they say to do ?? I know I don't always follow the 1K time frame but I have never been over 2K. It acts like grease is part of the dampining action of the tri-glide. Just curious if that could have some impact on your problem.
 

jbeletti

Well-known member
So Jim, had you been lubing all 9 zirks?;)

Ray and Jon - no :eek: Have not greased it for maybe 10,000 miles. I'll do better going forward :angel:

The pivot pin had some rust on it and no grease to speak of. I'd think it needs grease but see no way to add it. I did grease the shouldered washer thingies at each end of the tube before inserting the pivot pin.
 
Thanks for the information.
I usually give it a once over and make sure it is greased, but will do a little more in depth inspection now.
I have checked the torque on the bolts, when I check torque on the wheels.
Don't forget to check your wheel torque.
Mine call for 120 foot lbs.


Hockster
 
Jim, I noticed from your pictures that your King Pin needs grease also.
I keep the King Pin well greased, and when I get into my campsite, I have a locking sleeve that I install over the pin.
I use that when I have the coach stored, but also use it to keep from bumping into the greased up pin in a campground.
I make sure the grease is not contaminated with dirt, and if it is, I wipe it off with paper towels and install fresh grease.

Hockster
 

jbeletti

Well-known member
Jim, I noticed from your pictures that your King Pin needs grease also...

Hockster

Hockster,

Agreed - I have never greased my kingpin. Did it a few times on my first 5th wheel. Four 5th wheels later, guess I stopped doing it for some reason. I think I used something like white lithium ball hitch grease in 2005 on my king pin. What is recommended for the actual king pin itself?

Jim
 

porthole

Retired
Ray and Jon - no :eek: Have not greased it for maybe 10,000 miles. I'll do better going forward :angel:

The pivot pin had some rust on it and no grease to speak of. I'd think it needs grease but see no way to add it. I did grease the shouldered washer thingies at each end of the tube before inserting the pivot pin.

:eek: Grease required every 1000 miles, seems you were a bit short in the maintenance dept there Jimbo :eek:

After having a Superglide that did not use grease on the king pin I don't use it now.
Use one of the Teflon pin pad thingys and use the Slip Plate I had from the Superglide on the pin and the hitch jaws.

Nice and clean.
 

2psnapod2

Texas-South Chapter Leaders-Retired
:eek: Grease required every 1000 miles, seems you were a bit short in the maintenance dept there Jimbo :eek:

After having a Superglide that did not use grease on the king pin I don't use it now.
Use one of the Teflon pin pad thingys and use the Slip Plate I had from the Superglide on the pin and the hitch jaws.

Nice and clean.

How do you keep your Teflon pin pad thingy on? Mine falls off every time I unhitch.
 

JohnDar

Prolifically Gabby Member
How do you keep your Teflon pin pad thingy on? Mine falls off every time I unhitch.

It shouldn't fall off. When I removed mine from the Lippert pinbox to put on the 5th Airborne, I had to pry it off. There were two sizes of that pad, one 9" and the other 12", I believe. I don't know if the holes for the pin were different, though.
 

2psnapod2

Texas-South Chapter Leaders-Retired
It seems tight at first but after I pull and unhitch it is loose enough that it just falls off. I have been using the 12" one. Maybe give the other one a try then.
 

jnbhobe

Well-known member
How do you keep your Teflon pin pad thingy on? Mine falls off every time I unhitch.

Ok boys here's the trick when the Teflon disc falls off, Lay it on a hard flat surface, then take your trusty hammer and peen the inner fingers enough to make the disc stay on the pin. Pretty simple and you get to use your hammer for something usefull instead of getting mad and throwing it. LOL
 

jbeletti

Well-known member
How do you keep your Teflon pin pad thingy on? Mine falls off every time I unhitch.

Michael - I don't use a lube plate on the king pin. I have a permanent one installed to the 5th wheel hitch plate. Had them do it at Dually Depot in Elkhart. $52.95 with tax - installed.

For anyone - when greasing the king pin, does one grease the pin itself, the surface above the pin on the lower plate or both? And if using a lube plate, I'm pretty sure one does not need to lubricate the surface above the pin - but what about the king pin itself? I guess, technically, there is a metal on metal contact as the hitch jaws do wrap around the pin.

Jim
 
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