2wd fuse panel in 4wd

Need15

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Just curious if there was any difference from a 2wd fuse panel to a 4wd panel besides not having the the ground wire and the pink/ black wire that ran to the transfer case to light the 4wd indicator on the gauges. Both trucks are 79's.
 

Matt69olds

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I’m not all that familiar with the older glass tube style fuse boxes, but for the most part with the exception of fuse boxes for trucks with gauges or idiot lights, they are basically the same. The optional equipment a truck might have had its own separate harness that plugs into the fuse box.

I’m guessing a 4WD truck would have a seperste harness for the transfer case/ 4x4 dash lamp.
 

Strick

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I had to replace the fuse box on my 85 D30 (CUCV). They have a 40 amp fuse for the headlights that likes to melt. Typically the GM trucks don't have this fuse but the CUCV's do. They have a bunch of more junk because of the black-out features too. Anyway, I sourced a box from a 2wd C10 at the local boneyard. It was labeled differently but was set up the same or very similar. It took several hours to push out the spades from the old unit(s) and configure the wires into the replacement box. My advice is to be very patient. If you're over 6 feet (high or round) I would also recommend pulling the seat out as this will help with giving you room to move around.

Strickland
 

AuroraGirl

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Just curious if there was any difference from a 2wd fuse panel to a 4wd panel besides not having the the ground wire and the pink/ black wire that ran to the transfer case to light the 4wd indicator on the gauges. Both trucks are 79's.
Both 79s should have plastic fuses yes? In your case, I would say what trims and what GVW are both boxes from
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heres my 1980, k25(4x4 3/4 ton) gmc, with pretty basic optioning and some fuses/flashers removed at this picture. but the letters are good and i would guess its the same to a 79
 

Need15

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Both 79s should have plastic fuses yes? In your case, I would say what trims and what GVW are both boxes from
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heres my 1980, k25(4x4 3/4 ton) gmc, with pretty basic optioning and some fuses/flashers removed at this picture. but the letters are good and i would guess its the same to a 79
The 4x4 truck has no fuse panel so I have a 2wd parts truck that I took the whole wiring harness out of. They are both 79's but are glass fuses and not ATO style fuses. I think it should work, don't see any problems. Just gonna have to add the wires in for the 4x4 which won't be a big deal. Thanks forlorn the replies
 

AuroraGirl

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The 4x4 truck has no fuse panel so I have a 2wd parts truck that I took the whole wiring harness out of. They are both 79's but are glass fuses and not ATO style fuses. I think it should work, don't see any problems. Just gonna have to add the wires in for the 4x4 which won't be a big deal. Thanks forlorn the replies
The 1979 model year had plastic fuses. What does the panel look like? The 1978 model year had the most glass fuses and should be fine for your truck if it’s stock and not loaded with a ton of features. You may need to wire things differently. Fortunately the 1978 and 1979 aren’t too different electrically so it should be not too painful. The 1979 fuse box was like mine shown above.
 

75gmck25

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BLUF - in that timeframe I think the fuse panels for 2WD and 4WD were identical.

In ‘79 they were still using only the NP203 and NP205, and I don’t think there was any 4WD light in the dash. I know my ‘75 K25 has no dash light for 4WD.
 

CheemsK1500

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I assume they'd be the same, though there is a quite a bit of difference between the fuse panel on my '84 K1500 and '85 C10. I haven't looked at enough round eye squares to know if they'd be any different. With that said, if you're rewiring everything, you can use any fuse panel you want as long as there is enough slots for your application.
 

AuroraGirl

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BLUF - in that timeframe I think the fuse panels for 2WD and 4WD were identical.

In ‘79 they were still using only the NP203 and NP205, and I don’t think there was any 4WD light in the dash. I know my ‘75 K25 has no dash light for 4WD.
the NP203 , im unsure on the defining situation in what got it or not, had a LOCK or maybe it was HI LOCK light in place of 4wd. i think
The np205 also had a 4wd light starting some point
 

AuroraGirl

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"4 wheel lok"

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looks like np205 wasnt standard with that feature. my np205 (1980) is. but the 1977 Sm465/np205 I have, does not have a sensor on it
 

AuroraGirl

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I assume they'd be the same, though there is a quite a bit of difference between the fuse panel on my '84 K1500 and '85 C10. I haven't looked at enough round eye squares to know if they'd be any different. With that said, if you're rewiring everything, you can use any fuse panel you want as long as there is enough slots for your application.
1979+ was blade fuses but the panel was different every couple of years. the engine bay side for the bulkhead connection changed a few times to match this evolution
The fuse panel I posted would be OE on his truck, but the glass fuse from 78 is a fine one
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this is the albeit ****** pic of my 78 k10s box, it got paint on it by my gpa many years ago lol. but its got more fuses than a 75 would
 

75gmck25

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The 4WD Lok light listed in the ‘77 brochure really interests me. I would love to know what type of sensor they used to determine the shifter position on the NP203 and turn on the light.

Since my NP203 is unconverted, I just leave it in Hi position (AWD) all the time. I put it in the Hi-Lok position once or twice just to make sure it worked, but it’s been a long time.
 

AuroraGirl

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The 4WD Lok light listed in the ‘77 brochure really interests me. I would love to know what type of sensor they used to determine the shifter position on the NP203 and turn on the light.

Since my NP203 is unconverted, I just leave it in Hi position (AWD) all the time. I put it in the Hi-Lok position once or twice just to make sure it worked, but it’s been a long time.
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see the thing on the shifter assembly ? THe two wires run to a plug(prob connects to truck Id guess )
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