1995 to 2002 tach/cluster swap

[mudbogjoker]

I tried to put a cluster from a 2002 sport trac 4.0l into my 1995 ranger 4.0l and the tach reads lower than it should, i have an aftermarket rpm switch that has an rpm reading on it that is correct. Are the clusters not compatible or do i need to wire something up in the back of it. The higher the rpm the bigger the difference. (I have an aftermarket oil pressure gauge)