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Discussion Starter #1
My speedometer needle disappeared the other day, and the odometer stopped reading as well. I figured the speedometer in the cluster was shot, so I picked up a one from the yard. I took the yard one apart when I got home to swap the odometer with the one from my old cluster. I spun the speedometer input on the yard cluster and the needle moved, so I figured good enough for me. The speedometer input on my old cluster was super loose and easy to turn, while the one on the yard speedometer took a small amount of effort to turn. After installing in the truck, the speedometer and the odometer still do not work, but at least I can see the speedometer needle resting at zero now. Is the speedometer cable a part that goes bad often, or is this more likely just a dud speedometer?
 

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Lifelong S-10 Owner
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On the cable driven speedometers it is usually the cable that dries out and breaks. When you take the cable off the back of the speedometer head you can pull the cable out of the housing and check it.
 

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Gun Totin Redneck
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An easy way to test without pulling cluster is unscrew it of the transmission ans spin it there and have someone watch or spin it with a drill on low speed. Normally on older and miled up it is the plastic gear inside the trans that breaks or gets worn. Easy fix too, one bold pulls that off the trans and the gear is right there. As i recall that gear is under $10 and save you from pulling cluster. Could be the cable, however that cable is alot tougher than the gear.
335512
 

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Discussion Starter #5
I replaced that gear with a brand new one about a year ago when I swapped from 4 speed manual to 5 speed manual. Thanks for the suggestion though. I got a new cable in the mail today, on a 30 year old truck it doesn't hurt to replace it anyways. If that doesn't take care of the issue, I'll look into the gear. I also obtained another gauge cluster, in case I got a dud speedometer.
 

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Discussion Starter #6
I swapped in another gauge cluster and the speedometer cable, and the speedometer still does not work. I've got a new driven gear on the way. I pray it's the driven gear, and not the drive gear on the output shaft.
 

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Been there Done it
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The drive gear really isn't very difficult to replace if necessary. Just support the trans and pop the tailhousing off.
Oops, my bad. You said it's a 5 speed. Sorry.
 

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Discussion Starter #8
I took the gear housing off the side of the trans tonight, and both the driven and drive gears looked perfect. Before swapping in the new speedometer, I spun the input on the back to confirm it worked. Before swapping in the new cable, I spun the cable on the input end to make sure it also spun on the output end. When I took the gear housing off the trans tonight, I spun the gear and did not see any movement at all on the speedometer gauge. Do these housings go bad? The only ones I can find online say TH350, will they work in a T5 as well? They look pretty much the same...
 

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Gun Totin Redneck
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the speedo gear drives just the cable could be stripped on the drive pocket replace the gear, you cable on the cluster may not be seated fully as I recall it was a funky clip that was a tricky bugger
 

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Discussion Starter #10
I went back down because I thought of some more questions I still had unanswered that might help. I unscrewed the cable from the housing and spun it, which I had not done previously, and the needle on the gauge did move. I took the gear housing back out and pulled the gear all the way out and compared it to the new gear. They were identical in every way I could see. However, when I pulled the gear out of the housing, it had a piece of metal stuck on the end of it. All of the speedometer gear housings I'm finding online do not include the plastic piece screwed onto the metal housing, which I suspect is probably the true culprit. Does anyone know the name of it?

 

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Gun Totin Redneck
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oh yours is the step drive not straight through? in that case that is the drive gear pinion that has come separated from the gear inside the housing
 

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Gun Totin Redneck
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inside the black piece that screws to the housing. The black piece is a small gearbox that is used to correct or set cable speed so the speedometer reads correctly. I am guessing you will need to find that black gearbox, doubt if pieces are findable. A speedo shop could most likely repair it for you, or find it salvage yard or online.
 

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Discussion Starter #16
Good news: I removed the gear reducer from the speedometer gear housing and screwed the cable directly into the housing, and I know have a working speedometer. Bad news: The gear reducer was there for good reason, and my speedometer now reads 70 when I'm doing 50. Gonna tear down the reducer and see if I can figure out what went wrong, and if I can repair it.
 

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Or you could go to one of the gear calculators and figure out what gear you need and replace the blue one with a closer one. Or look up the part number on the reducer and see what it is designed to output and choose your new gear that way.
 

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Discussion Starter #19
I wasn't able to figure out the old broken reducer, and I couldn't find them anywhere new, so I ordered a used one on eBay for $47 shipped. Installed and now my speedo reads right on the money.
 
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