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Hello.

I have Neon, 2000 model with 3-gear automatic.

Whenever I accelerate, or engine is under heavier load, I hear a slight grinding noise from the transmission. Is this a problem or a "feature"? I bought this car recently, and I just noticed this.

The oil level seems fine, and color is Ok too. No burning smell either. I'm quite sure, that this sound really come from the transmission, not the engine. Problems or not?

Thanks in advance.

Hm, you shouldn't have that type of feature. Are you throwing any codes? Turn the key from acc to on three times, ending at the "on" position. If it says done on the cluster then there are no codes.

I'll test the ignition sequence next time when I'm going on the road and give the results. So far no codes have appeared.

Actually there is no problem (yet...) Everything works just fine. But I suspect that this noise is not something that is included normally.

It sounds a bit like you'd have little hole in you exhaust (which is solid and intact, no leaks --> no extra noises) Not a loud one.

Unfortunately if it is the ATX making noises, there will be no codes for it. It is not electronically controlled. You might want to pull the pan, and check for debris. A tablespoon full would be "normal", as long as it is not nice chunks of metal. A little clutch material, maybe some small metal filings, but not anything relatively large, like BB size.
If it does fail, the 31th is much cheaper to fix/replace than the 41/40te. (4 speed)

Is it more of a audible grind or can you feel a vibration as well? My exhaust leak kind of feels like grinding when the engine torques under load, but it feels like a vibration along with the noise.

Hi again.

I did the ignition test sequence, and I didn't get anything. No codes, no "Done" message either. (It should appear under the speedometer, right?) Hmm.

Excactly how do I "pull the pan"? What does this mean?

The noise is audible. No vibrations or shakings, just the noise. And the noise level is low, nothing ear-aching or screaming, just steady grinding.

If I have understood right, there is a turbine of somekind in the transmission. Could it be it, that's making the fuzz?

Turbine = Torque converter? Only thing that I can think they were refering to. I doubt it would be that, I think there would be noticable symptoms other than noise. Anything is possible tho.

The pan would be the underside formed sheet metal piece. IIRC, it has either 3/8" or 10mm head cap screws/bolts and silicone RTV holding it in place.

I can't recall for sure, but there may be an overrun/reverse sprag (lets the drum assy turn one way but not the other] Kinda like the starter pinion gear) if it is slipping under load it may cause some noise. There may be some bearings failing also. Pinpointing one thing via bandwidth isn't going to be easy.

If it is actually for sure the ATX.

I'm going to say it's probably diff pin failure (EXTREMELY common with these trannies, especially the 3spd).

Pull the backside diff cover off (10mm 1" bolts I think) obviously after lifting the front off the ground.

I'll bet you $100 you have a diff pin retaining pin that has broken and allowed the pin to come loose and grind against the housing. Usually this ends up causing total transmission failure due to the housing being comprimised, or metal shaving entering the transmission.

I am also in the process of completing my custom diff pin and limited slip attachment that will completely reduce these types of failures in all trannies with this diff. Pm me if interested.

I have had to rebuild 2 2000 neon 3spd atx diffs because of this issue. It is usually brought on by wheel spin in the winter months since the spider gears and pin is simple metal on metal the spinning causes the oil to leave the orifice and cause thermal adhesion of the 2 (or 3) parts together. Once one of the spider gears has welded itself to the pin, the skinny retaining pin cannot handle the stresses and breaks. In time the pin will start to eject itself out the side.

Alot of cars with this diff may have pin failure without any symptoms at all. This happens when the pin welds itself to one of the gears so good, that it simply cannot eject out of the side. This is still no good cause this will eventually cause the other gear to grab and they will fight back and forth (think friction) until the pin comes loose.

I suggest you DO NOT drive the car until you have at least put in a new retaining pin ($4 mopar part, spiders and main pin = $100+).

After you have installed a new retaining pin and main pin/gears(don't just do the retaining pin cause this will just cause future failure) remember to NOT SPIN THE WHEELS EVER AGAIN unless you have the money and means to install a real limited slip, or at least wait till my fix comes to life.

I hope this helped.

I had a similar problem, When ever I tried to accelerate my car would make a grinding sound. I did a transmission flush, after 130k+ I figure it was due, and the noise went away. I would try a transmission flush if you haven't, its pretty simple. Just have to drop the pan, change the filter, and refill .

Mat00ES wrote:I had a similar problem, When ever I tried to accelerate my car would make a grinding sound. I did a transmission flush, after 130k+ I figure it was due, and the noise went away. I would try a transmission flush if you haven't, its pretty simple. Just have to drop the pan, change the filter, and refill .

Was it a whining noise or a GRINDING noise?

grinding like something was slipping.