speedometer issues

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NCTyphoonKid

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the speedometer or odometer isn't working on my k5 has anyone else had issues with anything else other than the speedometer cable which i'm guessing is probably what it is.
 

bucket

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There might be a calibration box between the cable and the t-case, those are known to fail also.
 

NCTyphoonKid

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There might be a calibration box between the cable and the t-case, those are known to fail also.

What does that look like and is it available from advance?
 

bucket

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It's just a little pot metal box that goes inline with the speedo cable. If it's bad, just hook the cable right to the output on the t-case. You might end up with an accurate speedo for the current tire size or the size you end up running.
 

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The inner portion of the squarebody speedo cables are notorious for "popping out of place". Back in the 80's I remember dealing a LOT with this well known issue on my buddy's truck. Recently my K20 had the same problem, speedo failed.

To fix: simply pull the cable out of the rear of speedo. Put the rear end up on jack stands, place truck in gear and make sure speedo cable is spinning. Assuming it is, pull it out a tad to make contact with the speedo gearing. With a little adjustment, the speedo will be registering.
 

NCTyphoonKid

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I crawled up under the dash and the cable was unhooked, so I hooked it back up and its bouncing all over the place, so i'm guessing the cables bad
 

jetman

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The cable can be cleaned and lubed pretty easy by pulling out the inner core.
 

NCTyphoonKid

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The cable can be cleaned and lubed pretty easy by pulling out the inner core.

Does it just pull out and what's the best lubricant for it
 

HotRodPC

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Powered graphite is the best lubricant for speedo cables. Using oils or wet sprays just collects dust and junk turing the lube into jelly like **** that is bad news.
 

NCTyphoonKid

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I took it apart and cleaned it up and reinstalled it and it's still bouncing so I just went ahead and ordered a new cable and it'll be here tomorrow
 

NCTyphoonKid

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I got the new cable installed and the speedometer pegs out past 100 and the odometer isn't working
 

87ChevyR10

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I got the new cable installed and the speedometer pegs out past 100 and the odometer isn't working

Mine does that when it's cold outside. Makes a horrendous noise, too.

On a side note, I had a 1983 Pontiac Grand Prix with that speedo box under the hood. It was a PITA. No matter how much I cleaned and lubed it, it would always fail. Never knew about bypassing it though. Missed that car except for the crapped out 305. Bought it back in the 90's with about 40,000 miles on it. Later on, it would chuck starters and diesel horribly.
 

NCTyphoonKid

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Mine does that when it's cold outside. Makes a horrendous noise, too.

On a side note, I had a 1983 Pontiac Grand Prix with that speedo box under the hood. It was a PITA. No matter how much I cleaned and lubed it, it would always fail. Never knew about bypassing it though. Missed that car except for the crapped out 305. Bought it back in the 90's with about 40,000 miles on it. Later on, it would chuck starters and diesel horribly.

Idk what's wrong with mine I'd like to get it working that way I can track my miles
 

bucket

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Sounds like the new cable is binding.
 

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