77 tach needed
- Thread starter TBONE21
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Craig 85
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- Truck Year
- 1985
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- 454/TH-400/NP205
TBONE21
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- Tolliver
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Does the new one plug directly in? I think I saw where you have to buy a new wiring harness to make it work since the new tach is made from more modern technology. I swore I read that somewhere but I could be wrong
Craig 85
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I don't know. None of my trucks have ever had a factory tach. I'm sure the staff at LMC could help you.
75gmck25
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If your tach is like the stock one in my '75 GMC, the wiring harness is very simple. There is a 3 wire plug on the back of the in-dash tach, which gives you power, ground and tach signal from the terminal on the HEI. It is a separate harness from the large multi-wire plug for the rest of the cluster.
I don't know how a more "modern" tach could be wired any differently.
Bruce
I don't know how a more "modern" tach could be wired any differently.
Bruce
