I don't know if this should be in drivetrain or body so I'll start here.

I searched the threads and read a bunch of stuff.

My tach will drop to a lower rpm about 50% of the time. Idle at 400 go from reading fine to half the rpm. Most say it is in the cluster and maybe bad solder on these '06's.

How much is a new cluster? And does the odometer read correct from the ecm when the cluster is changed? Is it easy to change?

Maybe check the pickup on the balancer? My engine runs great and is not effected. So does the ecm use a different sensor than the tach? If yes maybe bad tach sensor? If no must be cluster or wiring?? Help! This will drive my **** mind crazy until it is fixed!!!

 

Subscribing!

 

Bump. Anyone? How is it wired? what's the best way to start diagnosing??

 

I thought my truck was idling pretty low... Like 500 rpms. I bet the tach is slipping like yours.