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Old 01-17-2010, 02:25 PM   #1
bikernut
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extra relay!

my 1987 K2500 4x4, 350, automatic has 2 relays up on the firewall, I know one is the fuel pump relay but I haven't found what the extra one goes to or what it is or was supposed to do, any body got an answer or just forget about it? thanks
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Old 01-18-2010, 12:01 AM   #2
ray_mcavoy
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Re: extra relay!

Hi bikernut,

I think it's a downshift relay for a TH400 transmission.

Ray
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Old 01-18-2010, 05:46 AM   #3
bikernut
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Re: extra relay!

nothing stops working when unplugged as it doesn't have any connector to plug into it, it is just there and I was wondering if I should be looking for some missing wires as my wiring diagram doesn't show it, but it is there and I have seen a few on both K1500's and K2500's with it and connected but that was a while back and didn't give it much thought until recently.
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Old 01-18-2010, 01:04 PM   #4
72 CustomCamper
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Re: extra relay!

Down shift relay. Should be #16...


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Old 01-18-2010, 08:58 PM   #5
bikernut
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Re: extra relay!

that sure looks like the little bugger but my truck down shifts with no problem with that not having any wires going to it. thanks
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