Transmission Whining

[Rochev]

I have a 2004 Mercury Sable with the ax4n transmission. It only has 130k miles. I just changed the fluid which is 8 out of 13 quarts, plus filter and pan cleaning. Fluid was gross but didn't seem too bad. The magnet wasn't that bad so I assume its been changed at some point.
I just bought it.

Anyways, ONLY when I'm on the gas, there's a faint supercharger type whine that starts at 30mph and goes until 45mph. When I let off the gas, the whine goes away within a second. If I hit the gas harder, the whine changes in pitch. Otherwise, it's the same 30-45mph.
Also, when the transmission warms up and the torque converter locks up, it shifts abruptly into OD and the transmission kind of shudders/jolta very quickly but not harshly. When cold (i never drive it stone cold) it shifts into 4th smoothly.
Fluid is at the right mark. My other ax4n has 237k miles and shifts like new. Not sure what's wrong with this one! Worried it's the torque converter going out, or just a bearing noise that doesnt mean upcoming implosion.

 

[Rochev]

Can't seem to edit the post. The whine is just like a trailer truck driving by in the distance. That's the only way I can describe it. I'm wondering if it's the tires making the sound, but it seems to be controlled by the throttle.

 

[dlundblad]

Did the whine exist prior to the fluid change?

Are you certain it's the transmission? Did you see if the noise existed while revving the engine in neutral?

Did you use the correct fluid?

 

[LeakySeals]

Its cold out. Maybe its just quieter now and you are hearing other noises cold, like the PS low on fluid.. or a wheel bearing.. or the front diff?

 

[Lubener]

Hopefully you used Mercon V fluid. I would drop the pan again and fill up with Mercon V and put some Lubeguard in. They make an additive which addresses shuddering. Those transmissions were famous for the teeth shearing off the torque converter hub and will stop in its tracks. If the converter hasn't been replaced, you likely will be doing it someday soon.

 

[Rand]

In my experience the last/latest version was more reliable but still had issues

Some of the issues were more common than others here is a partial list I found on google.

http://etereman.com/blog/ford-transmissi...hat-to-look-for

The one I experienced is they leak pressure at various places.. with the lower pressure things start slipping instead of being "locked" and then it wears out fast.

 

[Rochev]

Sorry for rambling and not giving enough info. Yes I Used Motorcraft Mercon V. There's no whine in park or neutral, and it's not the steering pump. The PS pump was also recently replaced.

It was making the noise before the fluid change but was quieter. I thought it was the tires at first, but it's controlled by throttle input. We had an arctic front after being 60 degrees last week, and it was about 0 degrees during most of my driving with the noise being most noticeable.

I know all about the notorious torque conveters in these, but I guess I got lucky with my other one. When it's hot outside, it sometimes revs up and slams into 2nd. That's the only issue I've ever had with that one. I can try filming mine but I doubt my camera would pick it up.
Specifically the noise starts at 28mph and keeps a steady pitch until 35 and starts to taper off. It comes back briefly at 45-50 but is much quieter.

 

[punisher]

If the whining started after the fluid/filter change it is likely sucking air at the filter/o-ring/gasket and causing cavitation. Cavitation can also happen when the filter is clogged.

 

[CT8]

Originally Posted By: punisher
If the whining started after the fluid/filter change it is likely sucking air at the filter/o-ring/gasket and causing cavitation. Cavitation can also happen when the filter is clogged.
With what we know I would +1

 

[Rochev]

I did change the filter and gasket too. It whined before but didn't seem as pronounced.
If it was actually sucking air through the filter housing, that wouldn't necessarily cause damage would it?