Guage cluster issue, help!

[RJack93]

So I've had my 91 ranger for about 3 months now. When i first bought it off the guy he said that the gas guage did not work so i figured a sending unit. Now the speedometer and tach fluctuate, some days the tach works but it doesn't register the right RPM's and the speedometer when im accelerating is all over the place. So i didn't know if it was a bad ground that involved all 3 of them or what. So if anyone could please shed some light on my issue that would be great!

 

[bduke23]

I am having the exact same problem. My truck is a 93. For me, the gas guage works fine but the speedo and tach are just as described. Tach always works, but is at the wrong rpm. Speedo bounces all over the place. I previously had been shifting according to road speed, but now that the speedo is acting up I can't even do that anymore. Really need to get this fixed, it is my DD. Does anyone have any insight?

 

[RJack93]

I read somewhere that usually when the tach and speedometer start acting up that it can be the sign of an alternator is going bad. The speedometer thing could be that your cable is loose, my father had the problem on his motorcycle with the speedometer bouncing all over the place then we looked at the able and it was backed off a little ways so it wasn't making perfect contact. Don't know if it's the same the ranger but it's worth a look-see