Hi, this is my first post here. I just purchased a 91 LX 5.0 for my daughter. The speedo bounces all over the place. My question is:
Will a speedo cable from a 5 speed work with a AOD. The previous owner has one from a 5 speed he will give me but neither one of us knows if it will interchange. Thank you in advance. Any help is appreciated.

 

Hello, and welcome to the site!

I am sorry I am not able to help much, but My '93 GT's speedo bounces up and down slightly at speeds of around 30 or higher. I have heard that the speedos are HIGHLY inaccurate at speeds past 80 or so. What I have heard to do is buy a speedo that can be calibrated. As far as the speedo cable from the 5 speed to an AOD, I am definately not sure. Someone here will know though. Ill keep this post bumped.

 

not sure about the cable but it could be an inccprrect speedo gear. If the rear gear has been changed the speedo will read off until the speedo gear is changed. See if the previous owner had the rear gear changed.

 

wow.. so im not the only one with the problem then... my speedo goes haywire at speeds of 120kms + just flip flops around

 

Very common problem....either replace the speedo gear or remove the cluster and get some powdered Graphite lubricant...pour it into the cable end and wash it down with a bit of WD-40 spray. A manual transmission cable with will with an automatic...you just have to be sure both are Cruise control or non-cruise cables....most are cruise but be sure both are the same as a non-cruise cable will not fit into the VSS(Vehicle Speed Sensor) at the transmission.

This problem is caused by a cable that is sticking or not properly lubricated.

 

Worn or damaged speedo gears can also cause the jumping speedo...

 

Theses pictures are from a 4 cyl standard and an automatic.
The trick to removal if your doing it yourself is to pinch the white plastic on the speedo cable. its a quick release type system. Most everyting else is snaps and plugs that cannot go but the right way plugs.

tools needed:
mostly sockets 8 or 10 MM i I remember right.
flat tip screw driver maybe a philips

My only after thought is if you replace the entire speedometer cluster?
Than try to get the exact year and tranny type.

I not saying it won't work.
It might work partially.

You will know its not 100% perfect when you get eratic post beeps from your cars computer.
This will be telling somethings not right.

 

That speedo clip is a ***** to get off the first time. Very tight quarters, barely enough room to get your hand in there to squeeze it. I used a set of needle nose the first time, as my hands are kinda big...