I have found a lot of threads that post exactly about the issue I'm having but there is never an official answer of what fixed it posted. I bought the truck back in mid Feb and now it's having this issue. So unfortunately I don't know the maintenance records of the truck.

Once the engine is warmed up to operating temp, there is this chirp that stays in time with the engine. With the occasional scraping noise. The scraping is not often, but does come and go with the chirp.

My truck has been at my local Dodge dealer for the last 4 weeks with them trying to find the cause. So far they have put a new cam and rollers and lifters in for both sides. Sent both heads out for new valves and cleaning. Flushed the cooling system twice, and changed the oil thrice. During all the work on the engine they noticed the idler pulleys, tensioner and water pump have all been recently changed plus a new serpentine belt. In addition the exhaust manifolds had the updated studs and gaskets. So it seems the previous owner was tracking the noise.

If anyone has had this chirp, or knows someone that has had this chirp and got it fixed, please me know what the solution was. Thank you

 

It's not the waterpump is it? They can make a chirp/light squeal just as they are warming up. The issue is the faces of the seal. They are so flat, they can set up a "ringing" noise like when you rub your finger around a wine glass. There was a rash of these when the hemi launched in '03, but never really went away. The pumps won't leak, but can have the squeak.
Mike S

 

It doesn't happen when it's starting or just warming up, it's only when the coolant is up to temperature. I would suspect that the water pump isn't the issue because it was recently replaced along with the belt and the idler pulleys.

 

Just as the coolant is warmed up is when the seal is most likely to start chirping/ringing. A brand new pump is just as likely to chirp as the original, as they are all the same (meaning they have the same seal). Only an aftermarket pump will have a different seal (the types of materials used in the seal faces). Fruedenberg-NOK makes the seals used in the pumps (at least thru '06 when I left the program). If the dealer installed the pump, they will be able to say yes or no if it's the pump & will replace it if that's the issue.
Mike S

 

That makes more sense than a pulley that only makes noise at warm temp. Would an after market gasket or seal work to fix that issue? I know in other manufacturers have rubber gaskets that seal. Or would I need a new after market pump?

 

The seal I am talking about is the dynamic face seal which all water pumps have (it is not a gasket). It is mounted in the housing behind the bearing and seals the bearing shaft from the coolant as the shaft turns. Not all seals will produce the noise. The possibility of ringing has been present since the hemi launched in '03. If you can't take it back to the dealer, the only other choice is to put up with it until it goes away (as deposits from the coolant build up on the seal faces, the problem will go away), or replace the pump again. Why did you replace the pump to begin with?

I don not recommend an aftermarket pump, as the seals used in the aftermarket are not as robust as those at the O.E. level (unless your talking about old vehicles....if you bought a Mopar pump for your 1995 truck, it would have an aftermarket grade seal in it....Mopar decided to cut costs). An aftermarket seal will average 60k miles (unless things have improved in the last 8 years I've been out of the business). The O.E. seal is good for 150k (unless the system has been abused).

Hope this helps,
Mike S

 

Thanks Mike. This does help a lot. I bought this truck in February and after my 2 hr drive home it started making this noise. I took it to my dealer and they diagnosed it as a bad lifter and cam. (Which the engine did have a bad lifter/roller and a damaged cam) so I paid them originally to rebuild the left side of my engine. I worked with the dealer I bought the truck from to assist as much as they could. Which was a refund on the truck price to cover half the rebuild cost. I got the truck back with the left side rebuilt, drove it to work and it made the chirp/sort of diesel sound. I then called the dealer, they took it back under warranty and they discovered a new part failed. They warrantied both sides of my engine to try to solve this chirp.

During this, they noted to me that the previous owner must have been hunting the chirp down because the water pump was newer, idler pulleys were newer, and the serpentine belt was new. The exhaust recalled was done and the manifold bolts was upgraded. They also have flushed the cooling system twice now.

 

If the noise is indeed the water pump, it will probably go away over time, but I know it can be annoying. When the hemi first launched and we started to get some reports of chirping/ringing, we put an alert out to all the dealerships to notify engineering the next time they had a customer complaint. The next one to pop up was in Los Angeles & I flew out with a couple Chrysler engineers to check it out. Since the dealers didn't have any replacement water pumps at the time I hand carried one thru the airport to LA.

We replaced the pump & brought it back to the test lab & spent several days with both Chrysler and F-nok to diagnose what was going on. We found out that the same seal was used in some Japanese applications & they also were having some chirping issues. F-nok was supposed to modify the finish on one of the seal faces to help the issue, but it never completely solved the issue. A fellow I work with just had to have his pump replaced in his 2016 dodge due to the chirping noise (warranty covered it).

As mentioned, if the noise is actually the water pump, it will have a "sweet spot" rpm where it chirps more than at other speeds.
Mike S

 

Ah. Okay thanks. This is a decent YouTube video that captures the sounds of what I hear from my truck at idle.


Does this sound like what the water pump issue sounded like?

 

Just a short lessen about water pump seals with a generic statement....all seals leak. The secret is to control the "amount" of leakage. The hemi launched with a seal containing one face seal made of silicon carbide and the other sintered carbon (if I remember correctly). The 2 faces are pressed against each other with a spring. Like any 2 materials rubbing against each other, they must be lubricated to prevent overheating and damage.

There is a delta between the pressure inside the cooling system and the atmosphere. The higher pressure coolant would love to escape thru the seal to the lower pressure of the atmosphere. Microscopic amounts of coolant do work their way between the seals and this creates the lubricant needed to prevent overheating (this is why you should never start an engine with no coolant in it....the seal will overheat & self destruct). The problem with the F-nok seal is the faces are so smooth and so flat that a bare minimum of coolant can wedge it's way between the faces. This sets up the condition known as "stick / slip" which is exactly what happens when you rub your moistened finger around a wine glass.

As coolant migrates it's way across the faces of the seal, trying to get to the atmosphere, it eventually evaporates the water and leaves behind deposits from the coolant and minerals from the water. These deposites slowly pile up & everything is good until one day when a chunk of deposits breaks away & creates a gap that allow coolant to flow thru. This is when you see coolant coming out the weep hole on the water pump to tell you there is a problem.
Hope this helps,
Mike S