Changing K5 tailgate to power window

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SDJunkMan

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The manual crank on my K5 is shot, and I am wondering how much trouble it would be to change it over to electric. Has anyone here done this swap?

There are a couple of K5's in the U Pull It with electric rear windows that I should be able to get parts from. Is the glass and regulator the same? Is there a separate wiring harness for the electric rear window, or am I going to have to make one if I decide to do the swap?
 

bucket

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I haven't done the swap, but it's a different regulator and a separate harness too, all the way up to the dash switch.
 

SDJunkMan

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I haven't done the swap, but it's a different regulator and a separate harness too, all the way up to the dash switch.
I figured the harness would have to be added up to the dash. I'm not sure if it is worth swapping everything out, but it would be nice to have the power window if I can do it for about the same price as replacing all of the manual window components. I know that there are at least 2 K5's that still have the parts in them at the Pull A Part. Was hoping someone had done it and could give me an idea of how much trouble it would be.
 

bucket

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There's really not much involved, other than running the wires and cutting the hole in the dash. You will need to get the lock cylinder keyed for your door key.

If you do the swap, I recommend wiring the dash switch to constant power, rather than ignition power.
 

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The cost is somewhat prohibitive for the process and if there is one thing I would recommend buying second hand (but in good shape) would be the motor if you can. Setting aside the parts you will spend upwards of about 500 plus dollars believe it or not and even then you need to make sure that the other parts for the window rail are in good shape (like the slide rails, roller tracks, and the tailgate window seals (inner and outer)). The new motors are really weak from most accounts and don't seem to do a good job of rolling the window up, much less down, and counter to what you might think, on the electric regulator it is spring loaded to to counter the weight of the window so the motor doesn't have to work so hard rolling up. Also, I would just skip installing the dash switch. Sure it is a luxury, but if you stop and think about it, chances are high if you are rolling the window up or down you are going to be opening the tailgate or putting something in the back, so if you are there, you can already just use the key switch and if it is all working well it rolls up or down in seconds. The inside electric switch can be found but there are no OEM ones so if you can find the housing I can tell you where to buy the switch. Not sure about the relay wiring to be fair because I actually just stomped mine by accident (while removing the body harness ironically) so I just ran a fused 10 gauge wire direct to it and in spite of what I thought it doesn't seem to help much to improve it's efficiency, but it is possible a higher gauge wire may help some (I doubt it though considering the motor pigtail only has 10 gauge leads) or the OEM motor really is just that much better. When I hooked the 10 gauge up directly I thought the window would fly up and down... Not the case so just a warning.
The motor I got was a cardone unit and I seem to recall it was very nice and new looking but I only paid about 70 bucks for it. I notice newer motors now cost 100+, so I figure if you can find the used motor in a salvage yard you will save a ton of money and it will probably work better, but to be fair I still need to replace my slide rails and rollers so that may have a ton to do with it as well.

Long story short here is your planned parts list for just the window rolling parts.

1 - motor (mounting screws will be needed get a working used one if you can, it will be cheaper and oem motors are almost always stronger. You can also take it apart some and clean and lube it if you are careful)
1 - jack screw assmebly (mounting screws will be needed)
1 - electric regulator (probably be able to use the mounting hardware off the old manual one)
1 - jack screw drive cable
1 - keyed switch assembly (mounting hardware may or may not be included)
1 - key escutcehon (You may be able to use the mounting hardware for the original manual escutcheon)


other parts you might need are

2 - glass channels (LH and RH) (side rails that align the window while going up and down - probably want to replace bolts because mine broke when I went to remove them)
2 - rollers with rivets (goes on the end of the regulator in the sliding metal channel that the window sits on)
1 - glass setting rubber (rubber sleeve that the window sits on and allows the channel to not vibrate and it snugs the glass up once installed - your old one will probably be rotted and ruined when you go to take the window out and it will bang around in the channel if you dont replace it. I was able to use some pliers and pinched the channel down to where it clamped on to the glass but I gotta figure it's not good for the glass and may cause it to shatter. Alternatively if you are thrifty you might be able to use some bike tire tubes but last I checked the rubber strip is actually cheaper so if you got kids with bikes maybe you have some old blow tubes. I didn't, lol



The manual is cheaper to fix or all out replace the electric if that matters to you and like I said, just not my opinion but I have heard others mention it seems like the new motors that are in the parts stores now days are garbage, but before I do that I am going to rebuild my tracks and the other sliding parts, just as insurance to make sure it's not the root of the problem and they will be useful for the manual conversion just as well. It would be nice to keep the electric window if it can work well. I always hated having to roll my window up manually in my 77 Jimmy.
 

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Glass is the same, regulator is not. You will need:

regulator with motor
wiring harness from the tailgate to the front cab
switch in the cab
chrome thingy from the tailgate (you can get it re-keyed)
and the switch from inside the tailgate.

Just grab everything that the harness connects to and you'll be good to go.

P.S.
If you're VERY careful you can rebuild the window motor by yourself and it will work like new.
 

bucket

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Like was pointed out, to piece the setup together, it can get very expensive. But if you have the whole setup available, it's kind of hard to say no to that.

Also, I use the dash switch in my Burb all the time. Actually, far more often than the key switch in the tailgate.
 

rpcraft

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Glass is the same, regulator is not. You will need:

regulator with motor
wiring harness from the tailgate to the front cab
switch in the cab
chrome thingy from the tailgate (you can get it re-keyed)
and the switch from inside the tailgate.

Just grab everything that the harness connects to and you'll be good to go.

P.S.
If you're VERY careful you can rebuild the window motor by yourself and it will work like new.


I definitely was not that lucky, lol. Not sure if I have any of the pictures of when I took it apart still but it was bad. Looked like a smokers lung after I got done dumping all the rust from inside. In my case the back window wipe/seals had huge cracks and missing chunks, enough so that water must have been getting in the window and going right into the motor.
 

SDJunkMan

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Thanks for all of the replies, I guess it's going to come down to what the U Pull it wants for the parts ( the complete aftermarket manual crank assembly seem like it is about $125) and what condition they are in. Either way ( manual or electric) I need to clean up and or replace the window guides and seals.

The tailgate has some rust through towards the bottom ( which seems to be common), that needs to be fixed. Every used tailgate I have looked at so far seens to have the same rust. I guess I'll try to fix the rust in mine, then decide which way to go with the window.
 

rpcraft

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To be honest you might be better off just going to Upull and taking the whole tailgate yourself or having them pull it. If they sell you all the individual pieces it will probably cost more.
 

SDJunkMan

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To be honest you might be better off just going to Upull and taking the whole tailgate yourself or having them pull it. If they sell you all the individual pieces it will probably cost more.
Good point, I'll have to see what they want for the whole thing versus the parts.
 

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