Gauges swap

[Sjaime71]

Hi, I have never been a member of any forum, so I hope I'm going about this correctly. I have a 1971 c10 LWB. It had the original 3 gauge dash bezel which worked just fine. I recently replaced the 2 gauge bezel to a 6 gauge bezel, but is not working correctly. None of the gauges work except the speedometer. The gauge lights only work when I turn the key to the on position. When I turn on the right blinker the the high beam indicator flashes. What do I have to do to make my gauges work correctly. I'm not very good with electrical so not sure what I need to do to make it work. Any input is very much appreciated.

[DeadheadNM]

You need to replace the old in-dash "dummy light" harness with one correct for the gauge cluster as the harnesses differ. The temp sending unit differs also IIRC (Lectric Limited http://www.lectriclimited.com/mainpage.htm sells ones that work). There may be more to swap under the hood - I'm sure others will weigh in.

[Lattimer]

Unfortunately, you can't just plug and play a gauge setup in place of the idiot light dash.

You have to do some rewiring to make it all work. Take a look here: http://www.gmcpauls.com/Tech%2520Tips1.htm
3rd item down gives you what you need. I followed it exactly when I swapped out my dash it worked perfectly.

You need to run a couple new wires, swap a couple of pins in the dash plug, and you need a correct temp sender for the gauge and an oil line to the gauge.

[Sjaime71]

Thanks for the input. I will try what you guys have suggested and post results.. Snowing and cold here in NM. So will wait till next weekend to mess with my toy. Thanks again guys

[Sjaime71]

My brother has an old 72 cab with a 6 gauge set up. Could I pull the wiring harness out and use it on mine or is it easier to cur the plug ang use it on my wiring harness?

[Lattimer]

All you have to do is move a couple of pins around and run 2 wires. It took my about 2 hours total. The pins pop right out with a small screwdriver. I wouldn't go to the trouble of swapping the whole plug or harness unless you have other issues that need to be fixed in the process.

[Lattimer]

And the plug itself is the same, its the just the order of which wire goes where is different. And of course there is 1 wire you don't use (oil light) and new ones to run for the ammeter.

[Sjaime71]

How do you know which pins to move around.

Ummm. Did you not bother to even read post 3 ? You really need no further info than that. If you need more than post three than you will need to take it to someone that can do it for you best of luck

[Sjaime71]

Thanks guys. I will be trying this fix this next weekend.