Speedometer stopped working (not speedo cable?)

[alkaline]

Hey all - happy to be making my first post on the forum. I recently got a '93 mighty max and overall it is running well - though I think it needs a new head gasket but that is another story.

When I purchased the vehicle the speedo worked just fine and suddenly stopped while on the highway. I figured it must be the speedometer cable but I received a replacement today and it did not work. By 'did not work' I mean I secured it to the transmission and observed that there was no movement at the opposite end of the cable when I drove the vehicle around.

I took another look under the truck and here's what I saw - which might be relevant in fixing the issue.

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I don't know the purpose of these two wires but they are attached to the transmission and emerge from the wiring harness. It looks like this has been repaired at some point. I assume there is power running through one of the wires, though I haven't taken a volt meter to them yet. Are they related to the speedometer? Any input on where to go from here is appreciated!

[pennyman1]

that is the reverse light switch- has nothing to do with the speedo problem. pull the speedo gear out and look at it-it comes out by taking the y shaped bracket off the side of the tranny where the speedo cable hooks up and spin the round housing out of the tailshaft.

[alkaline]

Excellent! I'll give an update once I take a look in there.

[alkaline]

Hmm, I was able to remove the bracket but the housing only moved maybe 1/4 turn before it froze up completely. I've got some penetrating oil on it. We'll see...

[alkaline]

No luck. Maybe I just don't have the brute strength or tools required, but I get the impression it should not be this difficult.

[Kmangas42]

Any luck?

[geezer101]

The cable bracket right next to the reversing light wiring looks like it had kinked the cable a bit. This could cause (or maybe already has caused) the cable and inner sleeve to wear out. I know this isn't the most fun job you can do but it might be worth your while to pull the entire speedo cable out and inspect it. I have never heard of the cable spline drive in the gearbox extension housing failing but there's always a first time...

[Jeff V.]

If the speedo gear unit is like other Mitsus, it needs to come out very straight. Rocking it side to side will only get it bound up in the transmission housing. The best bet, if you've got room, is to rotate it in the hole and try to pull it outward as it rotates.

[pennyman1]

did you get the right cable - the manual and automatic cables have a different cable end at the tranny, and the speedo won't work because it won't lock to the speedo gear.

[mitsubishikid]

So I know this post is really old post, but I had the same situation and I am certain someone else will down the road so here is how I fixed it, the cable was known to be good and so was the cluster, and the speedometer driven gear was also known to be good, in my case I was swapping to a different transmission I had gotten from a guy that had it rebuilt, it was a km145 from a 4x4 mm, again I noticed that the speedometer gear was in perfect shape when I removed it, but whoever rebuilt the transmission installed it wrong, yes you heard that right, you can pop it into the transmission a few different wrong ways, but only 1 way is correct if you can spin the key inside the speedometer gear housing, where the cable is inserted on the transmission, then it is installed wrong you should not be able to spin the speedometer gear if it is installed correctly and the plastic gear teeth are properly meshed to the transmission shaft.

[1fastcolt]

as usual nice find/fix Abe..

[pennyman1]

I had one where it was worked on and the gear was misaligned - tore all the teeth off the speedo gear. fortunately it didn't ruin the tailshaft gear,and I replaced the gear and I had a speedo again.