strange rpm drop

[randal07]

I know these trucks have a problem with the tach showing low rpm, mines been doing it since day one. It has gradually gotten worse to the point it's showing it idling at 100 rpm but as soon as I change the oil, the tach goes back to showing between 650 and 700 rpms at idle. Anyone know what's going on?

 

[SixOhh]

06's are notorious for bad dash's.

as far as the oil change .... that makes no sense!

put a scan tool on it, im sure you will see it is idling fine. time to buy a new cluster.

 

[randal07]

Yeah, I can tell that it's idling fine and I've heard about the dashes being bad. It just has me worried that I have have a lot of bearing material building up in the oil causing the sensor to show an incorrect reading and when I change the oil, it goes back to normal until I get around 1000 miles or so on it.

 

[paulb]

The crank sensor is external on an 06. The cam sensor is internal. Changing the oil doesn't make much sense to me, but you could tell be checking the rpm with a scan tool, compared to the dash. That would tell you if it's the dash or not.

The 06 dashes can easily be repaired. Do a google search and you will find info.

Paul

 

[randal07]

That's what has me confused, I would think it's a coincidence but it goes back to normal every time I change the oil. I have changed the oil at least 5 times since I noticed this happening and it goes back to normal every time.