Well I got my truck back...dealership didnt fix much of anything. They can't track down the vibration, (and want it back next week), and didn't look at the tach.

I talked with my brother (journeyman mechanic) and he is 99% sure it is a stepper motor in the tach. I guess I'll give that a shot and see where that goes.

 

I had not heard of a stepper motor before, so did a quick search and found this:
http://forums.trailvoy.com/showthrea...=stepper+motor

I know it isn't a Dodge, but it shed some light on it for me, hope it helps you.

 

I'm not surprised you found it on a GMC product. Apparently they are notorious for this kinda problem. My brother said dodge's very rarely act up, he said it will be the first one he's done in a dodge.

He may also get an electrical guy to do it, who works at his shop. Apparently he's a genius with this kind of stuff.

Hopefully it's as simple as that!

 

I have an 06 QC and on the way home today I noticed the exact same problem you guys are having. my truck comes to a stop and the needle will go to around 200 RPM. I did not notice an RPM change in the engine itself. Has anyone fixed this problem yet?

 

I had this problem with my truck before I bought it. To make a long story short I'd found this truck after several weeks of trying to find one with the specifications, year, options, and price I wanted. The only issue was on the test drive. Sounds like a similar problem. My tach rested at near zero at idle and appeared to be off while runnin through the gears. I really really really wanted this truck and although skeptic (as to how it was treated by its previous owner) I told the dealer I wanted it fixed before I would buy. He made a call to someone who told him he had just fixed the same problem on another Ram. Dealer told me it was a simple fix of just replacing the gauge cluster. After all was said and done, they claim to have replaced the cluster and I bought the truck. Had it for almost 6 months now and not even a hint of the tach actin up. I'd try replacing the cluster. Sorry, know this was long but hope it helps.

 

I'm not a fan of problems that "just fix themselves", but mine still appears to have done that?? I'll update when I see differently, but the only thing that's changed around here is the frigid outdoor temps, although I think it corrected itself before it got cold. It's been a few months now...

 

well looks like I will be pricing a guage clusters at a junk yard...lol, they are dam expensive at the dealer

 

Replacing the cluster is the expensive way of replacing the stepper motor for the tach. I'm fairly certain that a stepper motor can be easily changed, and are quite cheap. As far as I am aware, dodge does not list a p/n for the motor.

My truck is back at the dealership for a total of 3 days to solve my vibration issue. Of which I have heard nothing for the past 2 days. I informed them of the issue with the tach, and the shop foreman just checked the calibration of the gauges. (press and hold the trip, and turn the key to 'on', release trip). He said he figured the gauge cluster would need to be replaced. I plan to pull the gauge cluster, and have an electronics guy my brother knows to replace the motor.

 

If you replace you cluster be very careful to get an extact part number match and flash match. if the part numbers are incorrect or the flash is a different level you will have TONS AND TONS of problems caused by this. There are a few other threads on here about those horror stories. I'm going to live with a slipping tach and not spend the $$.

 

I'm having the same exact problem with my 06 quad cab hemi. The CEL came on about 4 weeks ago and that's when I noticed the tach issue. Gas mileage has dropped to 15, down from 18-20 depending on driving. I changed the EGR valve and replaced the gas cap. The tach is still dropping down to 200 rpm at idle and bounces around while driving. What gives?