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Hello, I own a 1969 Mach 1 “R†Code with an automatic and air conditioning. I’m having issues with my speedometer. I recently had to replace my aging cluster circuit board. The repair shop broke the clip holding the speedometer cable to the back of the speedometer gauge and installed a new cable. Prior to the new speedo cable being installed the speedometer gauge functioned properly. My first series of issues with the new speedo cable were as follows comparing my GPS speed to the gauge: 1. The speedo gauge needle would not move until I reached a speed around 15 – 20 mph. It would then jump up and gradually match actual speed. 2. If I maintained a steady speed around 50 mph the needle would slowly increase to 90 mph. 3. When I stop the needle would not return to zero but remain at around 15 mph. 4. When I jiggled the cable from inside the engine compartment the needle would drop to zero. I suspected a bad cable and returned to the repair shop. They replaced the cable with a new one. My second series of issues were: 1. The speedo gauge would not move until I reached 20 mph. Then it would begin to move upwards but never reaching or matching actual speed. Under 40 mph (gauge speed) the needle would always be lower than actual speed; e.g. gauge reads 20 mph and actual speed is 35 mph. 2. Maintaining a steady speed of 50 mph or more the needle would increase quickly to around 90 mph. 3. If I go over road bumps or railroad tracks the needle would bounce higher and lower and then steady itself after a few passes but never matching actual speed. This occurs more frequently at higher speeds. This was a new issue. 4. When I stopped the needle returns to zero. The repair shop performed the following troubleshooting steps: 1. Replace the speedo head gauge – no improvement. 2. Removed the inner cable and greased it - no improvement. 3. Replace the plastic speedo gear at the transmission – no improvement. 4. Inspected the transmission out gear – appears to functioning properly. I had no problems until the speedometer cable was replaced. Anybody have any ideas how to fix this? Thanks, Larry

Hi All, I have a couple questions regarding my recently purchased 1969 Mach1. I decided to pull out the dash to make some wiring and heater repairs. While the dash is out I'm going to send the tach and clock into the Tachman. 1) I removed the white collar of speedo cable from the back of the speedometer. Strangley the center cable will not come out of the speedo. I assume this is not normal. Do I just pull it out with brute force or is there a trick? 2) The Tachman is going to repair my clock and tach. I think I'll also have him do the 3-wire conversion on the tach. I read his site and it looks like the work he does on speedos is just cosmetic. If the speedo looks good and works is there any reason to also send in the speedo? Thank you, John