It is always a questions what to lube the speed cable with (the whole spring cable inside the casing). I have never found where you can buy speedo cable lube like the stuff that comes with some cable packages. I have never heard the ATF thing. Some lubes I have heard used are lithium grease, 3-in-1 oil, graphite, and gun oil. I have never tried any of these. The stuff I have used (speedo lube included in some kits) is a very light weight grease that stays in place better than oil. I wish I knew where you could buy it because it works well.

Some other things besides cable lube that can cause shaking are tight bends, melted or damaged casing, and speedo gauge. I personally have melt many a speedo cable on header tubes .

 

Well I took the plunge and bought the new cable and some lube. It really did not fix the situation under 40mph. Over 40 it made a big difference. I guess its the vibration of the engine? It was fun getting back under the car again so it all worked out. Thanks again guys

 

The die-electric won't gum up. It stays the same. It was a trick I picked up in a dealership and I've done a ton of cars with it. Old Buicks had the swinging speedo and were notorious for bouncing. This was about a 99% cure. The 1% were cables and speedo replacements. I still have a tube in my toolbox. It's an orange tube from Napa probably 20 years old.

 

Mine used to be really bad and when it was cold it would whip around and actually scratched the gauge face.

I have rebuilt the entire gauge cluster and new speedo cable etc. Mine still bobbles a little bit at low speed like less than 15-20. Is that normal?