6.2 Diesel Instrument Gauge Cluster Swap??

Hey guys. So I have an 82’ k20 6.2 diesel with a basic gauge cluster with idiot lights for gauges which I hate. I want to see my real numbers. So I got another cluster from an 82’ diesel as well with actual gauges but the pins for the gauges don’t match up.
I’d love an RPM gauge instead of the huge fuel gauge as well but I can wait for that if I have to.
Is there someone on this forum that has swapped this out before?

You may need to repin the connector since the two clusters use different printed circuits. I’ve never messed with a 6.2 diesel truck, but I have swapped out idiot lights for gauges with tach on my ‘80 gasser. You need to consult a wiring diagram from the reference section to be sure about what I’m saying.

For temp and oil you’d need to replace switches with senders. Now I’m going off memory here (always dangerous) there should be an orange wire on the cluster plug, #931, that is for the alternator idiot light. That wire needs to go bye-bye. A pink-black wire(s) going into the plug are ignition on power wires to feed the gauges when the key is on. They also feed the volt meter gauge.

When you repin the back of the connector, don’t forget to move the brake warning wire to its new location (Should be in the speedometer area.) Take your time and study the wire routes, and circuit board pathways before repinning the connector, you don’t want to have to do it more than once. Also consider testing each guage in the replacement cluster individually before installing, so you don’t end doing all of this for nothing. I haven’t had the best luck with used fuel and oil pressure gauges.

Thank you for your reply. How would I go about testing the gauges individually? Also, how could I obtain the circuit board pathway diagrams for each of these clusters?

TigerTodd said:

Thank you for your reply. How would I go about testing the gauges individually? Also, how could I obtain the circuit board pathway diagrams for each of these clusters?

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Because of changes between 73-80 and 81-87 I was mistaken about the orange wire in my first reply. There is no 1982 wiring diagram in the reference library here, 1983 is the the closest match. The pics below are the base cluster and cluster with gauges and no tach with the pinout. Go to the reference library on this form and download a copy of the wiring diagram because it also lists what all the wire and circuit numbers are.

As far as testing the gauges I don’t have that info off the top of my head. You could do a search for the subject. I’m sure it’s already been asked and answer on this forum.

TigerTodd said:

Thank you for your reply. How would I go about testing the gauges individually? Also, how could I obtain the circuit board pathway diagrams for each of these clusters?

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Not my video, but here is a good one for the oil pressure gauge. Also note that the little orange needle can be carefully taken about and reset if an oil gauge is not “zeroed.”


Here is another for fuel gauge troubleshooting/testing:


I don’t know how to test temperature gauges when they’re out of the truck, but I’m sure someone does.

I pimped out my mid 80's CUCV and replaced the indicator lights with silverado gauges. I used a multimeter to figure what each pin on the male plug did, then followed the copper leads on the printed circuit and matched them up. De-pin one lead at a time and label them especially if you're color blind like I am. Be sure to get the proper senders.

Rickf said:

I pimped out my mid 80's CUCV and replaced the indicator lights with silverado gauges. I used a multimeter to figure what each pin on the male plug did, then followed the copper leads on the printed circuit and matched them up. De-pin one lead at a time and label them especially if you're color blind like I am. Be sure to get the proper senders.

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I’m really thankful for your reply as you’ve successfully done what I’m trying to do on my diesel. Can you please expand on your answers? Which sending units need to be replaced and to which units? Where are they located? Basically a detailed road map on how you did the swap would be greatly appreciated.