Thread: Need Help Identifying Transmission Whine

Since the noise is present in every gear, and I assume while IN gear while sitting stopped, the only thing that is spinning in all situations is the pump and torque converter. Pumps very rarely are ever the cause of noise in these transmissions on their own, but a bad pressure control solenoid or boost valve or a few other parts can cause it to whine. There is a small bearing on the inside of the pump rotor that could also be at fault and cause a faint noise but again not really common. If the torque converter was making the noise it would get louder with a heavier load such as accelerating. I know you are pointing towards trans and your servicing the trans and adding a trans cooler appears to have had some effect, have you checked ALL of the engine pullies? Though the noise may even sound like its coming from the trans I have worked on numorous grand prixs with the non supercharged engine and before and after a trans rebuild the noise was present and after listening over everything with a stethoscope a few idler pullies are generally to blame. Im not saying this is the case for you, but a cheap stethoscope is probably $5-$20 and you can pinpoint exactly where the noise is coming from. DONT start with the transmission bellhousing area as all engine noises will carry through the engine and echo into the trans giving you a false sense of what is making the noise. Start with all the idler pullies on the engine, AC compressor on and off, alternater bearings, and power steering better be quiet since its new! After you check those and they are good then you are left with the trans. Here is something else you can try.... Once the noise is obtained while you are sitting in the drives seat pull the shifter into manual 1, this will create near max line presure and cause the pump to get loud. Does this noise sound like what you are hearing but louder? I appreciate the long post as it greatly helps out and I will do what I can to help out!

Just to make sure, you DO have this same exact noise whether in Park or Neutral OR sitting still with foot on brake pedal and in gear correct? If the same noise and volume of noise is present in any gear position and sitting still with your foot on the brake then it is likely servicable without remove the transmission completely which means removing the side cover should point to a problem. Once you pull the lever into reverse or drive with your foot on the brake pedal and not moving then nothing inside the trans spins as far as geartrain goes, so all that leaves is the pump shaft and pump.... you mentioned it didnt seem to get louder with load so we will not worry about the converter at this point. Now that "when" has been established and our possibilities I answer you questions in order

1. With your mileage there is likely a bit of wear on everything, but as mentioned above only your pump and pump shaft is spinning and working in gear and not moving, which you mentioned still exhibits the same noise. I very rarely see pumps fail in these transmissions unless a lot of metal is in the systme from internal damage. One thing I do see from time to time is a bearing inside the pump rotor in poor condition or falling apart. This will certainly cause noise and also tear into a sleeve/support that is pressed into the valve body and used for a guide for the rotor to sit on. When this gets pitted it will always make noise. The pump shaft itself more-less just floats and there isnt much that supports it or could cause noise, but he splines on the converter side will wear over time and should be replaced if worn. If the above is OK after apart and inspected you are left with the pressure system. The pcm controls the pressure control solenoid inside the trans and if it is bad or failing it can cause high line pressure which will also make the pump whine. Internal wear and overall low line pressure will cause the pcm to raise line pressure to overcome slippage from wear over time and if it is out of its acceptable limits then it will go into limp mode with max line pressure.

2. As mentioned above due to when the noise is present this problem should be able to be fixed just removing the side cover

3. The only obstacle is you will need some type of engine support to do this as you will have to hold the engine and trans up while lowering the support craddle from under the front of the car. Sometimes you can get away with just loosening the passanger side cradle bolts and completely removing the drivers side bolts and allow everything to relax at an angle to get the side cover off. Other than an engine support bar the transmission itself isnt going to require any special tools for what you can get into through the side.

Correct, noise is present in Park, or Neutral, or standing in gear, as well as while driving.

When I just flushed the trans and pulled the pan, I did not see any chunks of metal, only alot of grey mucky stuff near the magnet that I can only assume is about 135000 miles worth of friction material? That was all cleaned prior to reassembly, and it was all stuck to the pan around the magnet area.

Also, I dont know why I didnt mention it sooner, but when I did the trans flush, I used the trans to pump the old fluid out into a bucket while I dumped the new fluid in through the fill tube. It pumped so fast that by the time I poured a 1 gallon jug in through the funnel, it had already pumped out about 2 or 2.5 gallons. I had to shut the engine off to catch up. I had to repeat that twice. In total I used 20 quarts of trans fluid to do the flush, and refill the system after dropping the pan. I am going to ask if this sounds like the appropriate rate of fluid flow for an idling engine, but I'm not sure if thats enough information to guess on or not. And also, since the trans pump is clearly performing its job in this regard of moving fluid, would this point more to that bearing issue? Or will a failing trans pump still move fluid this well?

Also, is there a way to rule out the PCM before the side cover is removed?

While thinking about the relationship of temperature to noise, and it is very consistent in that it still makes no noise while cold, I am thinking that this lends itself to not being the bearing, and being more of a valve problem? Does that make sense, or am I thinking about it wrong?

Thanks again!