55.2-59 Urethane tailgate trunions

[NWA58]

Anyone have experience with urethane tailgate trunions? I finally have my truck painted and assembled, so still trying to fine tune and get to know what I have. Trailered it about 60 miles after assembly and when I got it home, the tailgate trunion bolts (essentially, the hinge) had backed out and were about to fall out. Tightened them up and did a couple of runs down the street before later taking a first drive on the “big road”. 10 miles round trip. Got home, pulled into the garage, found my tailgate hanging by a strap, and one of the Trunion bolts gone! The other was loose but still there.

I’ve got the first Mar-K tailgate they produced with the licensed GMC logo and push button latch. Now that Mar-K has closed their doors, my tailgate is irreplaceable. With the hidden latch, there is no need for chains and hooks, so those were not there to hold it up. I was able to reinstall the gate, and adjust the latches to be sure that both sides are secure. And to keep those pesky bolts from backing out again, they got a healthy dose of thread locker.

So with everything tight and bonded, I have a squeak from the urethane rubbing paint inside the roll when lowering the gate. I’m not sure if I over torqued the trunions and they swelled a bit, or they are just properly tightened and need some lubricant. I’m sure my Mar-K urethane trunions were produced elsewhere, as they are still sold by others. What are you guys using as lube in there?

[bowt1ed]

I know Energy Suspension has pre-lube for their Urethane bushings. Summit sells it for @5.

Cheers, Jim

[NWA58]

Good call, thanks

[dsraven]

if you have some synthetic brake lube that works too. its basically silicone grease you're looking for.
good call on the thread locker. was there a lock washer on it before?

[MARTINSR]

Good thing you caught that!
Brings back a SCARY memory of mine. I had my truck on a trailer for 700 miles when I moved to Idaho. About 600 miles into the trip right before going the last 100 miles where there are only 2 gas stations and NOTHING else I filled up the moving truck and checked on my beautiful truck on the trailer and found that I hadn't tightened up the tie rod on spindles! One had loosened up with only a few threads left and the front tire had turned a lot. The truck was held to the trailer with one of those over the tire straps! That tire strap was VERY close to falling off the tire! If that nut had fallen off the strap holding the truck on the trailer would have came off!
It still gives me the chills thinking about that!

Glad you didn't loose your tailgate! Most certainly good to check it, that was good thinking!

Brian

[Grey beard]

I bolted two oval shaped nylon trunions to the inside of my pickup box and slotted the right hand round hinge tube on my tailgate. The left end of the tailgate tubing slips over the left trunion and the right end of the tailgate tubing notch slips over the trunion when the tailgate is at a 45 degree angle. I have pictures but I guess I'm not smart to attach them to this posting. If someone explains how to send pictures I'll gladly sent them.

[1project2many]

Permatex makes a very good sprayable, clear, silicone grease. It's sold through GM as a GM branded item and it's also for sale as Permatex Superlube. Expensive but very good.
https://www.super-lube.com/multi-pur...-with-syncolon

[NWA58]

Good call on the Super Lube. I’ll give it a shot