Mazda: 1989 B2200 speedometer cable, speedometer cable, axle grease

Question
Brian, I read your list of expertise specialties and hope you can help with this pick up question or direct me to someone who can.  The truck makes a loud whining noise behind the dash and I believe it to be a bad speedometer cable, although the speedometer/odometer operates well.  I have 2 B2200 repair manuals but neither of them tell how to replace the speedometer cable.  Can you give me a little insight as to what is involved?  Thank you.

Answer
You're right, the speedometer cable is probably making the noise. I believe that your truck is still made by Mazda, so the speedometer cable should be basically the same as on other Mazda models. The cable can be unclipped from the back of the instrument cluster. I know it is difficult to reach, and even more difficult - if not impossible - to see, but it is located exactly in the middle of the speedometer. Release the cable from the instrument cluster by squeezing the clip on the connector and then pulling away from the instrument cluster. The cable should then pull rather easily through the fire wall. Be careful not to catch the clip on any wires under the dash. Follow the cable under the car and unscrew it from the transmission.

At this point, you can either replace the cable, or if you're feeling adventuresome, you can pull the cable out of the housing and lube it up. Technically there is a special type of speedometer grease, but I just use regular axle grease.

It is also possible that the speedometer is making the noise, but this is fairly unlikely. It is especially unlikely the speedometer would make noise while still functioning properly.