Adding 81-82 bumper fog lights

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,755
Reaction score
11,402
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
Guys... it doesn't matter where you tap power from, it's going to draw the same amount of power from the truck.. while more load will be on that circuit, doesn't mean the load will be different anywhere else and you can still get dim lights. As well as it's just a switched source, I can't tell you what it draws to turn on a relay but it ain't much.

It's personal preference, of when you want your lights on and off. From experience, turn on a few off-road lights and the stock rated alternator won't handle it.
Well that is true too, I don't disagree, but the point we are all trying to make is the pewny headlight wiring is designed for the headlights only. Give it a shot sometime, turn your headights on with alligator clamps hook a set of hella 550's to your battery and make note of how much your headlights dim, then hook those hellas into your low beam circuit. Guaranteed the amount of headlight dimming will be much more extra with the 550's drawing right of the low beam circuit. That wiring can't handle that much load. Ya, it'll still draw the same amount no doubt, it's just how much you wanna suck of the low beams your trying to improve to begin with. That's my prospective anyway.
 

PrairieDrifter

Full Access Member
Joined
Dec 28, 2014
Posts
3,853
Reaction score
5,646
Location
North Dakota
First Name
Mason
Truck Year
84,79,77,76,70,48
Truck Model
Suburban k10, bonanza k10, k30, k20, c10, gmc 1/2ton
Engine Size
350, 350, 350, 350, 350, 350
Well that is true too, I don't disagree, but the point we are all trying to make is the pewny headlight wiring is designed for the headlights only. Give it a shot sometime, turn your headights on with alligator clamps hook a set of hella 550's to your battery and make note of how much your headlights dim, then hook those hellas into your low beam circuit. Guaranteed the amount of headlight dimming will be much more extra with the 550's drawing right of the low beam circuit. That wiring can't handle that much load. Ya, it'll still draw the same amount no doubt, it's just how much you wanna suck of the low beams your trying to improve to begin with. That's my prospective anyway.
It was more of a preference. I didn't want to run wires and mount another switch for fogs so I just wired them into my marker lights, no more dim on or off. Always on with markers or headlights. I'd like to know what the sense wire for a relay really draws, because its just turning on a switch, it's not putting a load through that circuit.
 

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,755
Reaction score
11,402
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
It was more of a preference. I didn't want to run wires and mount another switch for fogs so I just wired them into my marker lights, no more dim on or off. Always on with markers or headlights. I'd like to know what the sense wire for a relay really draws, because its just turning on a switch, it's not putting a load through that circuit.
Can't be much, but I also can't think of a time I've needed to know (practically). At least in wiring to the parking lights instead of the actual low beam wire I bet you dim your headlights a lot less, but ya I get the ease of installation, or speed of installation sometimes is what is needed. Heck I've been sitting on a LMC headlight relay kit for several years now.
 

75gmck25

Full Access Member
Joined
Oct 13, 2016
Posts
2,263
Reaction score
2,206
Location
Northern Virginia
First Name
Bruce
Truck Year
1975
Truck Model
K25 Camper Special TH350 NP203
Engine Size
5.7
If you want to add more lights, use a relay to connect it into the headlight or marker circuits and use them only to activate the lights. It puts a load on the battery, but no more amperage is drawn through the old lights wiring.

Swapping a 94amp 12si v-belt alternator for your old 63 amp (or lower) 10si is a direct swap. All the wiring just plugs in and you use the same v belt. I recommend upsizing the charge wire from 10 gauge to 8 gauge, but that is not necessary to make it work.
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
6,970
Reaction score
12,220
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
It was more of a preference. I didn't want to run wires and mount another switch for fogs so I just wired them into my marker lights, no more dim on or off. Always on with markers or headlights. I'd like to know what the sense wire for a relay really draws, because its just turning on a switch, it's not putting a load through that circuit.
A small fraction of 1 amp iirc. You can look it up though.
Quick google says 30-100 mA.
 

Ellie Niner

Full Access Member
Joined
Aug 7, 2021
Posts
382
Reaction score
615
Location
Tucson, AZ
First Name
Tory
Truck Year
1986
Truck Model
K10 Silverado
Engine Size
LE9 305
I'm kind of late to this, but wanted to mention that it doesn't look like you've got anything that's going to perform very well for normal, on-road driving @Slooptin. I know a lot of people do fog lights because they look cool... but a fog lamp beam pattern is mainly for crawling along at 15-20mph, trying to keep it between the lines in a whiteout snowstorm or can't-find-my-ass fog. Though having a sh¡t ton of foreground light seems like it's helpful, it actually makes it harder to see out ahead once you hit about 25mph. The main headlights you've got installed right now aren't good. There are a bunch of those LED sealed beam replacements on the market, and all of the ones with the rows of emitters stuck in conical reflectors behind a clear lens just vomit light everywhere. Some of it might happen to land where you need it, but most of it doesn't. There are plenty of other options out there that are good... halogen, and LED; the legit LED stuff is pretty expensive. @SirRobyn0 did some successful headlamp fog lamp upgrades on his truck a year or so ago, and the Hella lamps he and others mentioned are pretty good stuff.

What you've got in the 1981-82 bumper in the first picture are just duplicates (at least optically) of the turn signal/park lamps mounted under the headlamps on 1983-up trucks. Those could be wired into your main turn signal/parking light circuit without any wiring upgrades... pretty much like connecting the extra lights on a trailer at the rear. The bright element (usually turn/brake) can be used as a DRL, if you're so inclined. Sounds like you're going with auxiliary lights in the bumper holes, and I'm guessing you already got the job done. Wiring up the relays to operate correctly would depend on what you installed i.e. fog, driving, aux low or high beam, aircraft landing lights...
 

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,755
Reaction score
11,402
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
What @Ellie Niner is saying about fog lights is true. I have a set on my truck Hella 550's and love them, but yea you gotta flip them off above 25 or you just don't see as far out. Here they are great on rainy nights when I'm driving curvy roads, especially ones I don't know well.
 

Latest posts

Forum statistics

Threads
44,162
Posts
950,639
Members
36,273
Latest member
dannyphx
Top