Back in the day(80s) we put vaseline on the speedo cables at the chevy dealer where I worked.
Always worked like a charm


91 Montero LS,3.0L,auto,off road pkg.
89 Trooper S,2.6L,5 spd
07 Dodge Ram 2500 4x4,5.9L Turbodiesel,6spd
"Non Vi Sed,Arte"