Koz

I decided to takle my speedo this weekend and came up with a few questions.

1.) What size is the bolt that holds the speedo gear in the tranny? I tried metic and standard and torques just for fun.. Nothing seems to fit?

2.) The tip of the inside cable was twisted :eek: and not just a turn or two but it looked pretty bad. Would you just replace the inside cable or replace the whole cable. I've had problems in the past with a jumpy speedo and I've tried greasing the outter cable, greasing the inner cable and so far it's not been jumping.. just about 20% off..

3.) Best place to purchace a new gear/cable ?

Appreciate the help! :cheers:


[Modified by Koz, 8:31 AM 7/7/2003]

BB68Vett

The speedo gear itself is held captive in a metal sleeve which fits in through the side of the transmission tail housing. The sleeve is held in place with a little metal tab which rests against a slot cut into the side of the metal sleeve. On my tranny (a Muncie) the bolt holding the metal tab has a 7/16" head on it. The metal sleeve also has an o-ring which makes it a pretty tight fit in the housing.

If the tip of the cable you refer to is the plastic end which fits into the speedo you probably should pull the speedo and have it looked at. My cable did the same thing and the speedo needed a rebuild because it was binding and twisting the plastic end.

I would replace the whole cbale, inside and out, just to avoid any problems. I would guess the Chevy dealer is probably the best place to buy one. By the way, if the cable is too long, it can be shortened. My cable was a foot too long and I took it to a speedometer repair shop and they shortened it for a nominal fee.

Koz

I just ordered a cable from ZIP.. $23+ It's both inner and outer.. Has anyone replaced this with the tranny in the car.. Any tricks.. I can't see where it goes through the floor from underneith but I'm sure it's not going to go too easy.. Thinking about taping the new cable to the old and pull it through from the top. Any suggestions?

Also, has anyone ever replaced the tranny speedometer gear on an '80. I need to know the size of the retainer bolt head.. Thanks!


[Modified by Koz, 2:48 PM 7/7/2003]

DougsL89

Koz - It's not that bad to replace on an assembled car. I think the hardest part was the dash connection. My cable is threaded at the speedo and tranny, and the connection at the speedo was too tight to loosen by reaching up under the dash. I finally had to "untuck" the top of the dash panel to get at it. The grommet at the firewall is nice and big, so when it is pulled out, it leaves a big hole to fish the new cable through. I would start from the right side of the engine compartment, and feed the cable behind the distributor and through the firewall into the interior. Make the speedo connection, and then snake the lower part of the cable under the car and into position. The connection at the tranny is cramped but doable. I would definitely replace the whole cable due to the price. My speedo used to bounce a full 20 MPH, now it is smooth and steady. I would definitely replace the firewall grommet. Good luck!

Koz

Thanks DougsL89.. It may sound stupid but I didn't even look in the engine compartment for the cable. I've had my inner cable out several times trying to lube it. My cable is pushed onto the back of the speedo and held with a spring type clip. I found it much easier to pull the console apart to expose the speedo from the front then attack from under the dash.. My hands are just too big and can't get enough grab on the cable to push it or pull it. I saw it go out the gromit in the tranny well and assumed it was going under the car on top of the tranny.,., I'll have to check again. It might be far enought forward that I can see/grab it from the engine side.. THANKS! :cheers:

BTW - do you know what size bolt head is holding the speedo gear in the tranny? Anyone with an '80 every do this?? I went through all my metrics and all my standards and nothing fit??? :confused: :confused: