'71 road runner 150 mph rallye speedo follies

[road robert]

Hello Mopar Tribe!

It started on Thanksgiving 2021 while driving avoiding highways from Holden, MA to Gouldsboro, PA. Suddenly I heard a loud growling sound that I could not tell where from it was coming from, then noticed the speedometer needle was dancing all over the place. It continued until I came to a complete stop, then the noise went away and the speedo needle acted normally. Then if I hit a bump or just random the issue would return until again I came to a stop, then Ok until it happened again... This problem disappeared for 1.5 years - 5K miles now it's back!

1. Does the speedometer unit require any lubrication after 52 years?
2. Could this be the speedo cable?

Thanks!

road robert

 

[allmoparparts67]

Hello Mopar Tribe!

It started on Thanksgiving 2021 while driving avoiding highways from Holden, MA to Gouldsboro, PA. Suddenly I heard a loud growling sound that I could not tell where from it was coming from, then noticed the speedometer needle was dancing all over the place. It continued until I came to a complete stop, then the noise went away and the speedo needle acted normally. Then if I hit a bump or just random the issue would return until again I came to a stop, then Ok until it happened again... This problem disappeared for 1.5 years - 5K miles now it's back!

1. Does the speedometer unit require any lubrication after 52 years?
2. Could this be the speedo cable?

Thanks!

road robert

Tried PM you your in box is full.

 

[JoePole]

Subscribed

 

[moparmarks]

Could be either the cable or the speedo head itself. I've have a couple speedos needing lubed. The 50 year old grease on the nylon gears dries out and the gears bind a bit. Is a real pain getting new lube in there.
Check and lube the cable first and see if that fixes it.

 

[71Beeper]

Moparmarks, how do you add lube to the speedo head itself?

 

[moparmarks]

Well that's the thing. You have to remove the speedo head from the cluster to get the lube where it needs to be.

 

[71Beeper]

Oh well, too late for me add some now.
I'm not going to take it apart t this point in the build.