I want to grease or lube the speedo cable on my ’87 Fifth Ave. Can you please tell me the best lube to use? I’ve heard graphite and I’ve heard white lithium but I’d like to hear it from the expert.
The OEM stuff, Mopar P/N 4318078 (the original 1950’s P/N was 1243642, the only difference was that the tube was metal, not plastic) is a very thick, waxy grease. The purpose of this consistency was to prevent the speedo needle from jumping around, especially as the cable aged and developed some lash. The Mopar number, unfortunately, was discontinued a while back (Mopars haven’t had speedo cables for 15-20 years) and the aftermarket stuff is oily graphite, which lubes fine but does nothing for damping. Therefore, I’d substitute the heaviest wheel bearing (“cup”) grease you have handy. One caveat: Apply the lube very sparingly to the upper 6˝ of the inner cable, to reduce the chances of the lube working its way into the speedometer itself, which would be disastrous.
