Speedometer Cable Removal

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dodgedart1968

dodgedart1968

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1968 Dodge Dart with Torqueflite

I'm trying to remove my speedometer cable to install a replacement. The first image is the installed cable. The second image is the replacement supplied by RockAuto.

I assume that I remove the installed cable by twisting the small cylinder adjacent to the large nut. It looks similar to the end on the new cable, but I would like to confirm the procedure before I start to avoid causing damage to the cable.

(The wetness seen in the image is from penetrant. The area was dry before I sprayed it.)

What is the function of the large nut?

20220314_144805.jpg

20220314_144935.jpg
 
I have heard said the nut is fixed to the cable on the old one.

The way I have heard it being removed is to remove the "fork" retainer and pulling the speedo gear ( back end of car up high and be prepaired for a trans fluid bath)

Then unscrewing the cable and nut from the speedo adapter.

If the reacenent knerled ring is free to turn on the sheithing then you could reinstall after the speedo gear is re installed, if not reverse the removal prosess.

NOTE before you remove it, take note of the pointer on the speedo gear holder/ housing. the housing is clocked depending on the number of teeth on the speedo gear.
 
Just unscrew the large nut (if it's frozen/rusted to the cable housing, you may have to remove the assembly as Dana outlined above), that is what holds the cable to the transmission adapter. Replacement cables often have a knurled nut instead of the hex nut- function is the same.
But beware that many aftermarket cables have an incorrect end on them- 5/8 instead of 7/8, I believe; they are listed as fitting, but they don't.
Correct 7/8:
Y-819_1__ra_p.jpg


Incorrect 5/8:
Y-881_1__ra_p.jpg
 
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IMHO, you have the wrong cable. That nut is not "fixed" to the cable it is free to turn against the flanged end of the cable, to tighten it into place.
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Thanks guys.

Yup, the new one is 5/8", so it's the wrong part. The nut is frozen on, and I can't get enough torque on my wrench to free it.

In lieu of messing with the adapter, plan B is to disengage the cable at the speedo head and pull out the center cable for cleaning/lubricating, and pour lubricant into the housing. Any thoughts on this approach?
 
dodgedart1968 said:
In lieu of messing with the adapter, plan B is to disengage the cable at the speedo head and pull out the center cable for cleaning/lubricating, and pour lubricant into the housing. Any thoughts on this approach
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All depends on the reason for wanting to replace it in the first place .


But that is done often enough (or should I say NOT often enough)

If we all did that every few years imagine the smooth speedos that would be out there
 
The speedo needle jumps wildly when the car is driven at twenty MPH. I assume that the cable is binding due to dryness/corrosion.
 
The function of the nut is to thread the cable onto the speedo gear housing. It does not come off the cable the aftermarket ones have just don't have the hex for a wrench. It still threads in the same spot as the original. I had to replace mine too. I don't like the aftermarket one id rather be able to tighten and loosen the nut with a wrench.
 
dodgedart1968 said:
Thanks guys.

Yup, the new one is 5/8", so it's the wrong part. The nut is frozen on, and I can't get enough torque on my wrench to free it.

In lieu of messing with the adapter, plan B is to disengage the cable at the speedo head and pull out the center cable for cleaning/lubricating, and pour lubricant into the housing. Any thoughts on this approach?
Click to expand...
Big hammer little hammer,big one on one flat,tappy tap tap with the little one. Not trying ti break an anvil here,so go easy.
 
Dana67Dart said:
All depends on the reason for wanting to replace it in the first place .


But that is done often enough (or should I say NOT often enough)

If we all did that every few years imagine the smooth speedos that would be out there
Click to expand...
Do that,dry graphite spray on botton 1/2 of inner cable. You dont want lube wicking up into speedo head.
 
dartfreak75 said:
Its not the wrong cable its just the way the after market ones are designed. I agree its a bad design
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He said the nut on the new cable is 5/8. That's the wrong size for his transmission gear housing. It's much bigger than 5/8. The speedometer head on the early A body is 5/8-18 screw on. That looks like what his new cable is for.
 
The original cable on my 52 Fargo is knurled, its nothing new.
 
RustyRatRod said:
He said the nut on the new cable is 5/8. That's the wrong size for his transmission gear housing. It's much bigger than 5/8. The speedometer head on the early A body is 5/8-18 screw on. That looks like what his new cable is for.
Click to expand...
Oh I see! I just went and checked mine its the wrong size too. Mine is also 5/8. I ordered the cable but haven't installed it yet. sure enough its 5/8 threads. I didn't realize they made these in two different sizes. Well crap now I gotta get another one. Good catch guys.
FYI I completely missed post #3 :BangHead::lol:
 
Chrysler part number for the 1968 dart speedometer cable is 2889783. Chrysler superseded the number to 3592360. This number can be found on eBay and from many Mopar vendors. It has the 7/8 fitting.
 
The cable core is out and cleaned. It wasn't dry or corroded, but the grease was degraded and somewhat sticky.
I plan to use a light coating of white general purpose grease to lube the cable.

20220315_163155.jpg
 
How did this work out? Did you just pull the cable core out from the speedometer end or remove the whole cable? Did you use white grease?
 
I recently had to pull my cluster to replace the temp gauge.

While out I gave everything a good cleaning and a bit of lube.

My gauge would do the following....

At very slow speeds, like barely moving, the needle would rise to about 5mph then pop to well below 0mph over and over again. At other speeds it would wiggle but not bounce

My old speedo cable had come in contact with the exhost tube and melted so I decided to replace with a new from Classis industries

The new one was almost identical to the old origional. Same length, same ends etc.

After reassembly of everything, the speedo acted the same way it did before cleaning and replacements except now it wiggles wildly (45 mph displays 40 to 50) at speeds.

While I was cleaning the speedo I spun it with the old cable, it seemed like the shaft that spins had a wobble to it. I assume that is the cause of my speedo issues


.
 
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