05 Suburban Tachometer Problem

My tachometer on my 05 suburban is reading 4000 rpms when idiling and goes up over 6000 when going 70mph. The engine is running normal rpms. What could be the cause of the tach not reading properly?

My tachometer on my 05 suburban is reading 4000 rpms when idiling and goes up over 6000 when going 70mph. The engine is running normal rpms. What could be the cause of the tach not reading properly?

that model year there was defective dash guages..check it out on the internet..

you may have to send it out to be repaired ...

that model year there was defective dash guages..check it out on the internet..

you may have to send it out to be repaired ...

The local radio mechanic said exactly the same thing today about the crappy instrument panels.