Door mirror screw inserts
 

I bought my 83 C20 many years ago and it came with holes in the doors for the old style tripod mirrors. The mirrors were not with the vehicle but the holes are still in the doors. I just have the standard 81-87 mirrors now.

I found what appear to be the same style swing out style tripod elephant ear mirrors at the junkyard. The mirrors look OK to me, but I can't figure out the threaded inserts on the doors. There appear to be threaded inserts with 4 metal tabs which crimp over the inside of the door skin. I can't figure out how those are secured. It must be some special type of fastening tool. I tried to pry the ears up but they are on there tight, and I can't see how I could get to most of them from the inside of the door.

Does anyone know what these inserts are and if there is a special tool to install them? I already have the holes in my door (except for the two holes which I think have the factory inserts under the current stock elephant ears. If I reuse the those two inserts, that would leave me with 3 holes in each door which would need need replacement inserts.

Re: Door mirror screw inserts
 

Yes, there is a tool to put the inserts in. It actually comes in a kit. I believe they are called something like "nutserts". We use to install them in the body shop. The tool looks something like a rivet gun, but also has a knob you use to smash the insert, from the inside, after it is in the hole in the door. The inserts aren't reusable. You can also use the factory screws, but put a washer and nut inside the door. I bet you can youtube or google it to find out more details.
Looks like Harbor Freight has a nutsert set.

Re: Door mirror screw inserts
 

I believe those are called a Jack Nut.

Re: Door mirror screw inserts
 

Is it like this - a rivnut tool?

https://www.harborfreight.com/45-pie...RoCCi4QAvD_BwE

Anything from HF must be good.;)

I assume that this is just a rivet with a threaded inside dimension - correct?

I am guessing that a bit of skill is needed in using this device, having never used one. I struggle with just a simple pop rivet gun.;)

Re: Door mirror screw inserts
 

i just bought a astro 1442 nutsert tool off ebay...a little better quality than cardboard freight..came with a bunch of different size serts..
we have this style at work and it works great...drill a hole for the sert to go thru...pull handles together and walla...threaded insert.

Re: Door mirror screw inserts
 

The stock holes for the dumbo mirrors are too big for a rivnut. I had to buy the reproduction ones from LMC truck.

Re: Door mirror screw inserts
 

Yes, those tripod mirror holes are big - looks like about 7/16" - 1/2" holes. Plus, the metal around the holes is cracked.

My original plan was to have the mounting holes in the doors welded up and ground down by a body shop, but since I found those trailer mirrors I thought that those mirrors would cover up the holes. If it is difficult and costly to get inserts in the doors to fill the holes and mount the mirrors, then I would go back to my original plan. I think the junkyard mirrors would be about $35 for the pair, and the passenger side mirror mount legs have a slight tweak to them from striking something.

The LMC nuts (p/n 30-0427) look like toggle bolt hollow wall anchors. Do you just tighten the screw which squashes the nut on the inside of the door skin? Are they big enough to fill up those big 1/2" holes?

Is it possible to have the holes welded and ground down to fix the hole problem?

Thanks.

Re: Door mirror screw inserts
 

My 81 had 13 holes in each door...evidently when the ripped a mirror off they just used a different one next...I had holes like yours...I welded up all the holes and started over...I used the lmc ones that have the plastic inserts...been 8-9yrs and they're still fine...
But even if you swap to the tripod mirrors your gonna uncover 3 holes behind the mirror youd be removing...
Whichever mirror you go with I'd just weld up the other unused holes...

Re: Door mirror screw inserts
 

They're jack nuts- you can get them at any parts store or amazon or mcmaster carr... they make coated ones with Raintite seal on them as well. I used these on my '74 to hold the big camper mirrors on, worked great.
https://www.napaonline.com/en/p/BK_6651059

Re: Door mirror screw inserts
 

Dang, NAPA likes to jack up the price for those jack nuts.;)

From what I could tell on the 84 Suburban which had the tripod towing mirrors, and the measurements I made, it looks like the two Dumbo mirror holes would be kept and the third upper hole on my door would accommodate the long three screw upper bar on the towing mirrors (5.25" center to center on the Dumbo mirror, then another 5.25" to the third hole overall, for a total three hole span of 10.5".) The lower two holes would line up with the lower bar of the tripod mirror - a total of 5 holes in the door. I think those trailer mirrors might have been a factory or dealer option because they line up correctly with the two Dumbo mirror screw holes.

I really don't tow hardly at all, so I don't "need" the trailer mirrors, but they are in remarkable shape so I hate to see them get crushed with that old Suburban. The even have what look like original blind spot mirrors which seem to match the profile of the larger towing mirrors. Obviously, these are old skool mirrors and stick out past the door even in non towing mode, but they do look "period correct."

I see a lot of great rust free vehicles go to the crusher at the local
Pull A Part. After a few weeks, they just scoop up an entire row of vehicles and dump them in the crusher. I have seen some late model vehicles with no body damage and paint in great condition go to the crusher. In the past two years old squares have disappeared from the junkyards. I suspect that people are paying more than scrap value (maybe $300) and that is keeping them out of the junkyards. Even junk squares are for sale for about $1500 on the local CL. 4WD squares are usually $2500 and up even if they are not running.

Re: Door mirror screw inserts
 

The napa items that MJN referred to, are exactly like the OEM ones I used when installing these mirrors when working for Chevrolet back in 1977. The 77 and up used metric fasteners but the same size hole in the door.

Re: Door mirror screw inserts
 

I was curious because the inserts in my door are cylindrical on the inside with 4 distinct "ears" which clinch on the inside of the door. It looks like the ones shown would produce a complete ring around the inside skin of the door, like a rivet.

Re: Door mirror screw inserts
 

Thought: If they are in good shape, you may want to scoop up the suburban doors before it gets crushed.

Re: Door mirror screw inserts
 

Nutserts or Rivet Nuts and tooling are cheap and easy to buy online.
I've used the plier type tools and the wrench driven tools. The plier tool is ok for aluminum riv nuts but when you're using steel rivet nuts you want the wrench driven tool.
McMaster Carr...
https://www.mcmaster.com/rivnuts
https://www.mcmaster.com/rivet-nut-installation-tools

Re: Door mirror screw inserts
 

For the purists, found this picture on the web