I have a 2010 TRX4 with 5.7L Hemi. I have a couple of issues (obviously minor in the eyes of the dealer) that annoy me. First, when the vehicle is in high gear with the RPM around 1200 - 1400, a light load on the peddle, the engine surges slightly until the RPM increases. The dealer blames this on the MDS system but the "ECO" indicator is lit when this happens.

Also, when the truck is idling there is a noticeable noise. Something like a bad bearing in the water pump or alternator. But the noise is not constant as you would expect from a bad bearing, but the pitch changes. Sounds like it is coming from the valve area on the drivers side. Dealer has looked at it twice now buit they say it's "just the way Hemi's sound ... think it's the valve train".

Anybody have any comments?

 

I have never own a hemi truck but i heard several people saying that the hemi engine makes a "different" sound.

 

Let me move this over to 4th gen Dodge Rams for you. Welcome to DF!

 

Majority of the time a bad bearing will make a squeaking or a grinding noise and will be variable in pitch as the engine increases and decreases in speed. Sometimes it will disappear after the engine warms up, sometimes get worse. If it is a ticking sound it seems some Hemi's will do this, also it may be a broken exhaust manifold bolt. Chrysler has an RRT out about these but I don't think it effects your truck. Still it is worth a look as bolts do sometimes break.

Another thing to check if it is squeaking is the fan belt. Maybe the tensioner is not working properly or a defect on the belt.

Surging sounds like it may be the trans just downshifting when you apply a little gas.

 

Both of the things that you have discussed here are seemingly normal for the Hemi. The Hemi does make a distinct sound, and from what you describe is exactly what my Hemi sounds like when idling same goes for my buddies Hemi's. And the "surge" you are talking about sounds exactly like what I notice when my truck's MDS engages. Many people cannot even notice when their trucks MDS engages, but I can feel it. It is just something that you will have to get used to. I don't mean to burst your bubble but your dealer is probably right.

 

Actually the noise can better be describes as a metalic chirping noise. Only noticeable at idle after engine warmed up.

 

i have that bad bearing sound at idle too. i have heard other 4th gen hemis with it too. to me it sounds like the exhaust is doing it. kind of a hollow, bearing ith no grease sound. i'm not too worried about it.

 

mine sounds like it has a belt squeak or bad bearing when its hot and idling. Been that way since it was new, its not bad enough where I ever took it in.

The surge may be the torque locking and unlocking, if it is doing it when you are holding a steady throttle there may be an issue. Try it with cruise control.

 

I've notice a slight chirp coming from somewhere under the hood. Not too loud and after reading this thread, I'm not too worried about... Whew....

 

My HEMI sounded just like any other engine from the from until they changed the manifold bolts now it makes a weird noise. Gonna leave it and see what happens. Extended warranty I will mention it if it gets louder and consistant I wasnt gonna fix that I knew I should have left well enough alone.