Question on rebuild...new wiring or not?

[70cst]

Ok truck lovers...as I was sitting here continuing my Truck 101 education...the thought came to me? When my truck is bing restored this winter....should I have all new wiring installed or keep the original. I know there are about a dozen manufactures out there...is one of them really a head above the rest as far as quality and ease of installation? Thanks in advance!

[ChevyC102007]

IMHO I would replace the wiring in your pickup. The original wires are at least 38-40 years old and may have alot of barespots yet uncovered that could cause problems later down the road. As stated in another post youll be kicking yourself for not replacing the wiring after the truck is back together (and its probably gonna be TONS easier to replace the wiring with everything apart.)

As for wiring kits Ive heard alot of good things about Painless wiring kits for ease of installation. Everything is marked as to were it goes and comes with easy to follow instructions and a new fuse box that uses the modern blade style fuses. The down side is $$$ cost, The Summit racing catalog lists the full 18 circuit GM truck wiring kit for $319 dollars plus tax and shipping (if applicable) Im sure though someone else on the boards can point you towards either a board vendor or other source for wiring harness kits.

Just my .02 cents

[PanelDeland]

40 year old wire with brittle cracking insulation.Has probably had stereo,trailer and other accessories wired in at some time.Along with hardened brittle Grommets.Yeah, I think that's the way to go!

"NOT!" I always figure if it's worth doing it's worth doing right.There are some things to consider though.What style of truck are you building?A fairly stock truck can use an OEM style harness while a full on custom will probably require a few extra curcuits and may need to be hidden as much as possible.Budget should also play a role.OEM style harnesses are available from most of the BB vendors as are the aftermarket style.You will need to have a plan so that you can let them know what accessories you will be running.
To answer your original question,yes replace the harness.

[70cst]

As far as what type of truck...it will be close to stock w/o a lot of mods. I have added pertronics....otherwise it will be close to the way "electrically" that it left the factory. It now has 5 lug verses 6 lug but not many other changes have taken place. I look at my budget and all the work translates into $$$ but sounds like this would be a well spent investment. Thanks for you replies thus far.

[myoldchevytruck]

I would recommend replacing the harness as also suggested by the previous posts. There are allot of manufactures out there selling great harnesses and those selling not so great harnesses. A good OEM replica harness is the M&H.
Vendors such as GMC Paul sells this harness.

[hdflstf]

Replace if you have a mind to. There are so many potential gremlins and intermittent problems lurking in the old wiring. Cracked or broken wire strands. Cracked, worn, brittle, missing insulation.

[cdowns]

i'd first clean(gojo works great) and inspect the original harness and see exactly what you've got if in fact the wire is rotted and cracking replacr it but if its not then i see no reason to spend hundreds for a replacement if all it needs is a little attention i've reconditioned meny wiring harness in the 50-60 year old range that are still working fine

[orgalmeister]

$300 or so is cheap insurance to keep your truck from burning to the ground. Ask my neighbor who almost did that to his '55 shoebox.

[TotalChevy1]

Originally Posted by cdowns

i'd first clean(gojo works great) and inspect the original harness and see exactly what you've got if in fact the wire is rotted and cracking replacr it but if its not then i see no reason to spend hundreds for a replacement if all it needs is a little attention i've reconditioned meny wiring harness in the 50-60 year old range that are still working fine

i would recommend inspecting it first, I just did that I was actual very suprises at the condition of the wiring. 90% looked new, especailly the stuff that was still wrapped. I cleaned and re-wrapped. Did have a couple areas were they had been modified but that is fixable. Even the engine compartment was 100% sound.

[ChevLoRay]

www.wiringharness.com is an excellent resource for part numbers and availability. That is the website for M&H Fabricators. I've used them and they are very good to help with technical questions you may have.

There are many vendors on here who sell their products. Catalogs from M&H are free.

[mrein3]

Like cdowns and TotalChevy1 have pointed out, I would fix what you got. Here is a secret that will save you a ton of money.

Go to your local NAPA and ask for part number 725147. That is the NAPA part number for the brass colored wire terminal (female) inside 99.9997% of the electric connectors in your truck. The male terminal part number is 725145.

After inspecting wires, if you see a patched, cracked, or frayed wire, simply find both ends, slip those terminals out of the harness, measure the correct length of the correct colored wire, and replace it.

You can buy TONS of those terminals for a couple of pennies each. I keep a handful of both male and female ends in my electric box at all times. You never know when you may need to fix a wire. Lowe's, Home Depot, Menard's etc. all carry many different colors of different size wire.

For what its worth, I use WAY more female ends than male ends. Which makes sense as the back of switches, your headlights, and relay connectors all plug in to male spades.

I just typed those part numbers into NAPA on-line. They are available but "must be purchased from your local NAPA Auto Parts Store".

[BigSky71]

Do it! I didn't look forward to installing my painless 18 circuit wiring kit, but once I got into it, I was surprised how easy it was.

[David Flores]

Anyone hear anything about EZ Wiring harnesses? Good? Bad?

[70cst]

Thanks guys...this is good info.

[chip46wis]

My 2 cents----I really thought my wires were in good shape---a good friend that works at the world famous Muscle Car Restoration here in town made a good point----for under $200.00 get new wires so all that hard work doesnt go up in SMOKE.
I bought a EZ2wire for around $200.00 NO it is not installed as I am not at that point,and yes I am lucky if I reach a snag I have several of the top Rodders-mechanics as good friends.

[Longhorn Man]

I've only owned 4 of these trucks... and they were all worked hard most, if not all there lives. Every single one, I inspected and repaired any problems, which were far and few between.
The aftermarket is making billions of dollars off the FEAR of electrical repairs. It's real easy stuff, and odds are, you don't need to rewire the whole truck.

[kxnomore]

If you do replace the harness (which was a no brainer for me as my trucks had rat's nest wiring) look at the Harnesses sold in the Classic Parts Catalog made by American Auto Wire. I bought one from them that was an absolutely perfect match. It went in so nice and had ALL the right plastic gutters, wire ends, colors, heat proof wrapping, etc.

I also installed a "painless" kit in another truck that needed all sorts of fittings and grommets installed and such. And it didn't have the wire ties in the right places, and basically took way more time and effort. But it did cost about half...