Balky (rusty) tailgate latch on GMC pick-up

[Captain Dirty]

Apologies in advance for posting automotive maint. problem on a tractor forum, but I have been a member long enough to have some feel for the credibility/reliability of the answers on this forum that I would not have as a newby on a PU forum.

The plastic handle on the tailgate cams against 2, flat steel bell cranks that rotate in opposite directions on a pin or rivet. The other end of each bell crank is connected by a rod to the actual latches in the tailgate at the sides. The bell cranks are returned to their original position by springs in the latches themselves.

Periodically, the tailgate fails to latch. Disassembly reveals rust on the flat surfaces of the arms, under the head of the pin, and on the bracket to which the assembly is pinned so that the arms do not return. My fix has been to spray penetrating oil on the area and begin exercising the arms and pin. Once somewhat loose I add Marvel Mystery oil and continue exercising. I am reluctant to use a heavier oil or grease that I feel would attract dirt and gum up sooner. Of note, the handle ends of the rods are rusted, but the latch ends are not. I suspect water is entering between the sheetmetal of the tailgate and the plastic trim ring around the handle. Would a dab of never seize on the upper side of the arms and pins work to shed any water dripping on the mechanism?

 

[Gregster613]

Apologies in advance for posting automotive maint. problem on a tractor forum, but I have been a member long enough to have some feel for the credibility/reliability of the answers on this forum that I would not have as a newby on a PU forum.

The plastic handle on the tailgate cams against 2, flat steel bell cranks that rotate in opposite directions on a pin or rivet. The other end of each bell crank is connected by a rod to the actual latches in the tailgate at the sides. The bell cranks are returned to their original position by springs in the latches themselves.

Periodically, the tailgate fails to latch. Disassembly reveals rust on the flat surfaces of the arms, under the head of the pin, and on the bracket to which the assembly is pinned so that the arms do not return. My fix has been to spray penetrating oil on the area and begin exercising the arms and pin. Once somewhat loose I add Marvel Mystery oil and continue exercising. I am reluctant to use a heavier oil or grease that I feel would attract dirt and gum up sooner. Of note, the handle ends of the rods are rusted, but the latch ends are not. I suspect water is entering between the sheetmetal of the tailgate and the plastic trim ring around the handle. Would a dab of never seize on the upper side of the arms and pins work to shed any water dripping on the mechanism?

Geeze, A dad of anti-seize - just put it on and see. It can't do any worse.

 

[Roadworthy]

A wire brush and WD-40 rubbed in should help with the rust. As far as lubricants go I wouldn't use grease or oil because around her dust would gather making the problem worse. I like graphite or molybdenum disulfide for a lubricant. Both are dry powders.

 

[Racer4]

I’d just get it loose with penetrating oil and movement, then put a few drops of engine oil on the pivots. A little dirt accumulation won’t hurt anything. Beats a seized up dry one any day.

 

[OldTrix]

Find some waterproof grease and cover them generously. That should help prevent more rust buildup. I wouldn't worry about them getting gummed up, given the use case and tolerances of the connection.

 

[pmsmechanic]

As a part of every oil change I lube all the vehicle hood, door, trunk hinges with WD40. Also all the door, hood, trunk and tail gate latches. I have a lot fewer problems if I do that.