Gauge question

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rwljpl

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I’m planning to put a tach where the big gas gauge is and put a small gas gauge where the clock is. Has anyone done this? Any tips?
 

rwljpl

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I see LMC sells a printed circuit. Is that something I needfor this?
 

75gmck25

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In the stock cluster the large printed circuit has electrical connections for the gas gauge and a brake warning light, and it connects them to the large plug on the end of the cluster. I assume that the add-on printed circuit makes the proper connections between the stock circuit and the new tach/gas gauge. You could probably make the connections manually with new wires, but it depends on how handy you are with wiring and reading diagrams.

The connection for the tach on an original cluster is a three wire plug that does not depend on the printed circuit board, so I assume the new circuit is for the gas gauge and warning light connections.

I have a tach cluster in my truck and have found that original tachs are a little flaky sometimes. It appears to be a problem with solder connections that goes bad in the original boards. There are many kits out there to fix the 70's tachs in Corvettes, using a new circuit board on the back of the original tach. However, the board on our trucks is not the same, so you can't fix an OEM truck tach with the Corvette board.

I think there may be other online vendors who sell the tach/gas gauge upgrade, but I'm not positive. LMC is always fairly pricey, but sometimes its the only source for special items.

Bruce
 

andym22

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You will need a gauge cluster with a tach in it, as the cluster with the big gas gauge will not accept the tach, the back needs to be cut out for the tach to fit and the circuit board is different. I purchased a tach cluster on ebay, just look for one that will work with your oil gauge (mechanical or electrical) there is also a difference between 2wd and 4wd clusters. It's an easy swap as the wiring does not change its plug and play. You'll need to run a new wire to fuse block, ground and distributor from the tach. I wound up replacing the tach with one from LMC, as 75gmck25 mentioned the original tachs are flaky.
 

CiscoKid

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I was having issues finding a temp sensor that worked with Vortec engine and factory gauge. Considered aftermarket gauges but cost was high and retrofit looked like a PIA. Ended up buying Intellitronix digital gauge set on sale for $200. Has 5" tach where old gas gauge was and the new circuit boards/gauges screw into existing mounting holes. Nice 5" tach is going to cost $100 to $150 anyways. Love the new setup.
 

rwljpl

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Thanks Andym. How does tach connect to fuse box? That’s one part I have not seen instructions for.
 

andym22

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Thanks Andym. How does tach connect to fuse box? That’s one part I have not seen instructions for.

Tach just plugs right into switched ignition spot on fuse block, the tach harness already has the plug on it, very easy.
 

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