89 RS, speedometer is jumping and ticking all over the place. I got the replacement cable. Now...disconnecting it from the tranny isant gonna be a big deal already had a look but from the top right under the brake booster im not sure about? How am i suppose to get down there to detach it what do i use? If anyone has a how-to or any tips on how to get this done itd be very helpful. Thanks

-Steve

 

I would like to know a good place to purchase a cable, mine burned up in a fire. I believe you have to go under dash, disconnect from pedal and push the rubber stopper through the firewall.

 

I'd try cleaning and lubing the original first. Pull the cable, flush the housing with brake clean until the fluid is clear, then relube with Sly-Glyde, a lube for speedo cables among other things. GM still sells the cable.

JamesC

 

autozone, 7$

 

It unscrews from the transmission.
To get the other end, you don't have to drop the steering colum but it will help alot. You can wedge the cluster into the colum and dash if you can get to the back of the speedo you can get the cable off. It is very tight like this though and if you are unsure of what you are doing I would recommend droping the steering colum so you can see what you are doing.
On the back of the speedo you have a metal tab that you have to push towards the speedo if I remeber correctly, may have to pull it away. Then the cable will pull out of the back of the speedo.
Then pull it through the firewall. You may have to get under the car to put the new one thru the firewall. Once you do that it should just push into the speedo, then screw it into the tranny.

 

i just replaced mine. there is a tab on the frame rail, im not sure what size of bolt but theres a bolt in that tab. once you unscrew the bolt you will have access to detaching it. its a 2 part cable im sure since you prolly have cruise control. my cruise control didnt work so i just eliminated mine and pulled the speedo cable off a 70's camaro. anyway like i said get that tab off the frame rail and youll be able to get it. its kind of a bitch to get its tight as helll usually. and behind the speedo theres a metal tab around where the speedo cable goes in. push that tab in and pull your cable out. you wont have to drop the steering column but you willl have to remove your fuze box out the way. pull the cable through the little firewall. if your rubber piece comes off with it (it should) then try to force it off the cable, or just take a razor blade knife and cut one side of it so you can take it off the cable, pu your rubber piece back on the new cable and put it back through the firewall. to get the new one installed on the speedo just get your hands behind the speedo and feel for the metal ring and in the middle of the ring youll feel right where the cable goes, just snap it back on and your golden. make sure you put your cable back under the power brake booster again. theres gonna be 2 metal tabs on the frame rails. theres another closer to the tranny, just follow the cable up towards the engine and youll find it. if im not mistaken i think its a 10mm bolt. good luck!