So my speedometer on my 91 has not been working lately. It sits at 0 mph and occasionally floats around 40. I unhooked it on the bottom end and hooked a drill up to it, and still got nothing.

I bought a new one, and started looking at how its routed into the cab. It disapears under the dash, and I can't figure out how to get to where I can unhook that end. Can anyone give me some pointers here?

 

Well, obvious to you is the dash comes out towards the wheel. Some models have the trim around the edge that just pops out with a little prying from the back of trim.

 

If you're replacing the complete cable (not just the drive cable) you need
to remove the dash cluster.

Disconnect the negative battery cable.

Remove the headlight and windshield washer *****. Use a small
flat blade screwdriver or pick. On the end of the ***** is a slot
where you pull outward on a metal tang. This will release the ****
from the shaft so the **** can be pulled off.

Pull the left bottom trim bezel off which is snapped on. If you have the
dual tank selector switch you can leave the bezel hanging or unplug
the electrical connector.

The bottom right trim bezel has torx bolts near the steering column that
need to be removed before you can pull the bezel off.

Remove some more torx bolts and the bezel that surrounds the dash
cluster can be pulled off.

This will expose some more torx bolts that hold the dash cluster in
place. Once those are removed pull the dash cluster towards you
as far as you can. The speedometer cable will only allow you to pull it out
so far.

Reach in back of the dash cluster and unplug two electrical harness plugs.
One on each end of the dash cluster. You push on a tab and the connectors
will pull off. They are keyed on.

Then disconnect the speedometer cable by doing the following.
At the end of the speedometer cable is a white tab that locks the cable
in place.

With your finger press inward on the tab. At the same time
pull the speedometer cable off the cluster.

Here's a picture of the white tab you press inward on.

The second picture shows the end of the speedometer and the
groove the white tab locks into. When you push the tab inward
the opposite side of that tab unlocks from the groove.

 

I've been away from this project for a while, and have just looked back here.

I have to say, you are amazing. Thanks for the detailed info. Going to go work on this today.

 

Well I managed to get the cable replaced. However I tested it with a drill before I put it back together, and the needle stayed at 0. I suppose the speedometer itself is shot...

 

on mine i decided not to mess with it and my gps that i picked up during christmas time for around 70$ tells me my speed within 1-2 mph.. and i normally don't even use that.. once you have driven the vehicle a bit you know what rpms means about what mph.. cheaper solution for me because knowing my luck as soon as i take the dash apart something else in there would break and need replacing..

 

That's a good idea, I hadn't thought of that. This truck has been mostly sitting in my shop for the past six months, but when I do drive it, I use the tach and the flow of traffic to just wing it. I'll look into a gps, it's about time I got one anyway.

 

Just for clarification's sake, I followed this extremely helpful post, and I thank the author profusely.

But, with my wrist scraped to hell, and my index finger black and blue, I finally discovered this small point of difference. If you push, with all your might, on the cable end of the clip, you hurt your finger. If you push, without very much effort at all, on the speedo side of the clip, it slips right off the speedo head.

 

Thanks to the original poster and the above editor. My '90 is as the editor indicated.


I don't think I would have figured this out without the help.

 

Thank you for the detailed explanation and photos, exactly what I was looking for.