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What did you do with your GMT400 today...or yesterday....

Big T

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I too would like to know how to replace the hinges and still get proper alignment. sure would have been nice if they left them bolt on instead of welded in place.

I suppose it would be a lot of work, but one could pull the door off, then drill through the hinge and pillar, cut off the old hinge and use the holes as a template to drill the new ones . make a backing plate to go inside the pillar for support with the same holes drilled. then bolt it all together and be done without welding them back. even once everything gets drilled, the holes in the pillar could be egged a little for minor adjustments like the old trucks had, also tack weld the nuts to the inner plate.

The existing hinges appear to be welded on. How would you remove them? Grind them off?

How would you get access to inside the pillar?
 

MrMarty51

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The existing hinges appear to be welded on. How would you remove them? Grind them off?

How would you get access to inside the pillar?
This was/is a terrible design.
There is dimples in the hinges at the approximate location where the spot welds holds them on. Drill all the way through hinge and body. A 3/8ths bit IIRC BUT I am not sure on that size.
Then I use one of those good old fashioned Snap On gasket scraper that has the wood handle. Grind back the handle a ways to keep it from splitting while being pounded on with a sizable hammer. Yup, them scrapers double as the best and thinnest chisel ever created.
Chisel along between the door frame and himge until what remains of the spot welds lets loose.
Nuts are held on the inside, upper and lower hinges and bolts threaded through the hinge, the door frame and into the nuts.
I dont remember if I match drilled a plate to the hinge pattern then welded nuts to that and shoved them through the holes.
Just too much bridge under the water since those days.
 

dbrannon79

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I haven't tried accessing the inside of the pillar where the hinges are, but I think the lower can be accessed from behind the kick panel cover and the upper one would be the hardest but it might be accessible with snaking your hand up in there through the lower part of the dash.

same with the door, they were bolted on with three bolts and had a backing plate. for those to access, the entire door inner panel with the regulator would have to be taken apart.

the older trucks had a plate in there that had three nuts welded to it in those areas with the holes in the pillar slotted for some adjustment. the plate would fall of you weren't careful. I remember having to replace hinges on those ones lol the plate would fall and go below the floor pan and was a PIA to get back out!
 

Big T

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I haven't tried accessing the inside of the pillar where the hinges are, but I think the lower can be accessed from behind the kick panel cover and the upper one would be the hardest but it might be accessible with snaking your hand up in there through the lower part of the dash.

same with the door, they were bolted on with three bolts and had a backing plate. for those to access, the entire door inner panel with the regulator would have to be taken apart.

the older trucks had a plate in there that had three nuts welded to it in those areas with the holes in the pillar slotted for some adjustment. the plate would fall of you weren't careful. I remember having to replace hinges on those ones lol the plate would fall and go below the floor pan and was a PIA to get back out!

I'm going to try new bushings and pins first as a cheap interim solution. Thought about it (while fishing) and I can use ratchet straps from joists in the garage to hold the door for this work. Light week of work, so I pulled the drift boat out (other bay is filled with appliances for the new kitchen) and the Suburban is in place for the work.
 

Will L.

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You should not need to replace the hinges themselves unless there has been a crash.
Even at that usually the pillar gets bent and has to be made straight to correct it.

If you have to replace hinges: remove pin, remove door, then you drill out where the spot welds are in the hinge. Proper method is then to reweld the hinge on. Rather than doing that or gaining access to the rear, I would use HIGH QUALITY nut inserts. then like mentioned use it he old hings as a template to drill the new hinge. Oversize the new hole 1/8” & use nordlock washers so vibration never is an issue.
 

MrMarty51

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Yeah, drilling off the hinge half would be only if the bushing bores of the hinge plates is totally hogged out and would no longer hold a bushing.
Be nice if a bushing bore shim kit was made so the bores could be enlarged, a bushing pressed in and then the original bushings could be used.
 

Big T

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Got the door hinge bushings and pins done:


The roller door positioner is bent, so I ordered a new one. Not sure how it comes out.
I ordered this as the existing roller is bent:

B672454B-4720-49C5-844C-101C7E90B920.png
In the pic on the end opposite the roller they show a c-clip that holds it in. On the truck they mushroomed that end and it looks almost like a Phillips Head. There is no c-clip. Do I have to grind that end off to get it out? This was in the first post which started this entire thread.
 

dbrannon79

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@Big T that head will need to be ground off and then punched through so the pin falls out. best to do that when the door is off. on mine I had to really put some force on the pin to get the new one in place.

oh on the bushings, they do make oversize ones but are expensive compared to the normal kit that doesn't last long. all 4 of my doors all ride on the striker bolts even after replacing the bushings. doors have very little up/down play but they line up with the body lines when closed. not sure if there is a fix for that. driving on a rough road you can hear the "bam , bam, bam" when the latch mech is bouncing on the striker bolt.
 

Big T

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@Big T that head will need to be ground off and then punched through so the pin falls out. best to do that when the door is off. on mine I had to really put some force on the pin to get the new one in place.

oh on the bushings, they do make oversize ones but are expensive compared to the normal kit that doesn't last long. all 4 of my doors all ride on the striker bolts even after replacing the bushings. doors have very little up/down play but they line up with the body lines when closed. not sure if there is a fix for that. driving on a rough road you can hear the "bam , bam, bam" when the latch mech is bouncing on the striker bolt.

I'll have to do it with the door on. I'll use a dremel, maybe a carbide grinding bit. Or cut the pin in the middle and knock the pieces out each direction.
 
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