Best way to splice multiple wires
 

Hey guys! I'm working on my tail lights and I have 5 wires I need to splice together. One wire is the lead from the switch. The others go to my upper and lower tail lights on each side of the truck (I have lights in the bed rail), and one wire to the license plate light. What would be the best way to connect these together?

Strip them all back, twist and solder them together and heat shrink them?
One large wire nut?
Some kind of terminal block? Concerned about it getting wet.

Re: Best way to splice multiple wires
 

Soldering and heat shrink is by far the best way IMO. Much more secure than simply crimping connectors. Most I've ever done is 3 into 1 so Rather that soldering all 5 into 1, I would solder a couple together at a time and work my way into 1.

Re: Best way to splice multiple wires
 

Soldering was what i was thinking of doing. The lights I added into the bed rolls are what complicates things, as it adds 2 more wires to the splice. Otherwise it would just be the 2 tail lights, and the license plate light.

Re: Best way to splice multiple wires
 

I would not solder the connections, No wires used in cars are soldered. They are all connected using male and female solder less connectors. You can buy solder less connectors that support multiple wires. And yes you can get them that will bridge them together if needed.

Re: Best way to splice multiple wires
 

GM has used soldered crimp connections for decades so yes soldering is ok to do.

Take a single strand of say, 10ga wire maybe 6" in length and wrap the bundle of wires together in opposite directions tightly. Then, solder the connection fully and slide a section of dual wall polyolephin tubing over it and slowly heat it until the sealant starts to creep out of each end-fully soldered AND sealed now!

Re: Best way to splice multiple wires
 

Now that's friggin genius!

Re: Best way to splice multiple wires
 

Thats a very solid connection. Solder!

Re: Best way to splice multiple wires
 

I use un insulated connectors and heat shrink them. Most manufactures don't solder, crimped terminal ends and junction points.

I was told by a race team/ Custom car builder group I was working for not to solder, at least in the race car, makes for to stiff a wire and will break at soldered joint.

Re: Best way to splice multiple wires
 

In high vibration areas ( I dont think anybody on here regularly BAJA races their daily) properly strain supported wiring is something to consider-then and ONLY then if solder is to be used it should not go under the crimped barrel. MIL-spec wiring applications for a passenger car/truck is not needed or required. Crimping is best for physical strength and soldering is best for electrical strength so I prefer both.

Re: Best way to splice multiple wires
 

Ive always used the epoxy filled wire nuts, and then tape over them to provide a strain relief on the wires.

I did the EFI 5.0 Transplant on my 74 bronco in '99 and havent had any issues with the epoxy wire nuts.
just tape over em so no one will see them and say youre not supposed to use wire nuts on automobiles.

they are far superior to crip or butt connectors
but then again just twist and tape is better than a butt connector

Re: Best way to splice multiple wires
 

Compliments to that one! That is one slick way to make a be all end all solution.

Re: Best way to splice multiple wires
 

I've never seen a factory soldered joint (I have seen 67-72 brazed joints though), and 100% are crimped. I agree that soldering creates brittle connections that tend to fail if not supported. I've worked w/ electical/electronics stuff for longer than many on here have been alive.

Do you know how to solder?

If you're going to solder, make a good mechanical connection first (as in crimp), and make sure the soldered area can't vibrate later or you invite failure.

Most people who offer opinions understand the cosmetics of for example making an electrical connection, but not the realities, or actual electrical and reliability requirements for use in a moving vehicle.

I challenge anyone to show a factory soldered joint.

Re: Best way to splice multiple wires
 

Ok challenge accepted: So since GM never used soldered crimp splices would you like tontake a stab at what GM vehicle this stock wiring is from Franken?

Re: Best way to splice multiple wires
 

Ok times up. While it is odd that GM did this crimp/solder method typicaly in 1 spot in the firewall harness, 67-88 A and G body vehicles (Chevelles, Monte carlo, Malibu, Regal, etc) had this crimp soldered connection to join the AC relay feed wire to the alternator voltage sense wire and the charge wire to the starter. As for why? I really dont know other than it must have been the most economical way for GM to assemble the main engine harness for these cars. While it would have made more sense to just go ahead and route all leads to the starter lug vs using a solder crimp, I dont think it would have been easy to pass all those wires through the metal heat sleeve-the 73-up trucks dont have this problem because they use a common firewall junction which makes a whole lot more sense! Why GM didnt do this on passenger cars I dont know.

The pic is from one of my Monte Carlos in storage (1980 model) and Ive built countless custom harnesses for these cars as well. Contrary to what people have opinions on with regard to a soldered connection-it is NEVER a failure point-the AC blower relay feed connector inside the 4-cavity packard connector gets hot over time and it will literally melt the connector housing cavity to the point of complete blower speed failure. This is an unsealed connector and corrosion is the usual culprit here.

But, Ive never seen OEM soldered crimps ever fail-and I have seen standard crimp connector failures over and over again-anybody troubleshooting LH power window switch connectors from 77-87 can surely attest to that-I know I can lol!