95 ka24e speedo problem

[akurtzer57]

I know these are famous for the speed sensor quit. My odometer doesn't work. The speedometer will go above 0 when take off. Going down the highway about after 20miles it will read 60-70 or so. And sticks there even when come to a stop. Soon as shut the truck off speedo drops to 0. I Unplugged it and I does go above 0 when driving. The transmission code is fs5w71c same as 240sx 300zx. Has anyone tried using the speed sensor out of a 240/300zx. I know they have different final drive. Which might cause speedo to be off. Reason Im asking I can rob the speed sensor out of my 300zx to try and see if it works. Just want to make sure its the sensor not electrical or in the cluster before dump money on a new one. I can't believe it just quit at 52k