Speedometer stopped working in my '79
Melting Slicks
Joined: Jun 2005
Posts: 2,938
Likes: 2
From: Arkansas
That would be the first place I would check, if you have cruise unhook it at the transducer and/ or transmission and see if the cable moves freely.
If it does it's ether in the speedo gear housing or the speedometer itself.
Those aren't too hard to troubleshoot, good luck
If it does it's ether in the speedo gear housing or the speedometer itself.
Those aren't too hard to troubleshoot, good luck
Pro
Joined: Aug 2007
Posts: 707
Likes: 31
From: Pitman NJ
I just
had the same problem with my '79. If you have cruise, the transducer goes bad and starts to put more tension on the lower cable until it breaks, thats what happened to mine. I also heard that GM doesn't make this part anymore, and the aftermarket ones are junk.
My guess, is that it is the lower cable (if you have cruise), it's also easy to change. I would put in one cable.. and bi-oass the cruise (assuming your car has it)
Open the door, and kneel outside the car. Reach your left hand under the dash until your find the cable. Go toward the speedo, and there is a metal tab. Push that tab, and it will release the cable from the speedo. From under the hood, pull out the cable, and a rubber grommit will come with it. Put the grommit on the new cable and fish the cable back in the hole, and it snap it back on the speedo. Put the gommit back on the firewall
The bottom of the cable screws onto the transmission. Put the car on ramps, or jack it up and route the cable where the old one was.
I did this last week, it took about an hour. If I had to do it again, it would take about 15 minutes.
My guess, is that it is the lower cable (if you have cruise), it's also easy to change. I would put in one cable.. and bi-oass the cruise (assuming your car has it)
Open the door, and kneel outside the car. Reach your left hand under the dash until your find the cable. Go toward the speedo, and there is a metal tab. Push that tab, and it will release the cable from the speedo. From under the hood, pull out the cable, and a rubber grommit will come with it. Put the grommit on the new cable and fish the cable back in the hole, and it snap it back on the speedo. Put the gommit back on the firewall
The bottom of the cable screws onto the transmission. Put the car on ramps, or jack it up and route the cable where the old one was.
I did this last week, it took about an hour. If I had to do it again, it would take about 15 minutes.
