Today as i was pulling a trailer home. I heard a squeal as i pulled away from a stop sign. Not sure what it was but i looked the truck over at home and found nothing. Later in the day I drove it down to my dads, (7 miles) all was well but when i got there as i pulled up to his shop and stopped It started squealing again....?? At this point we started looking it over again and this is what i know.

Truck is an 85 W350 crew cab, 360, 727. At idle everything sounds good in park and neutral. Put it in gear it starts to wine and squeal. but only in gear, forward and reverse. Jacked up the back tires. As long as the tires are turning no noise. As you start to apply the brakes it will start to squeal and gets louder as they come to a stop. IT sounds like its in the front of the trans/ converter area.

It sat for a few hours and I drove it home. It shifts firm and when it did it would chirp and make a small squeal that went away as the speed increased. on every shift. I put it in neutral and rolled into the yard with no noise. Hold the brake and put it in gear.... it starts squealing again. At this point I will park it until I find out whats wrong.

I think when the converter is stalling its squealing. Any thoughts on this? What could this be? Does this theory make sense?

Put it on jack stands after getting it hot enough to start squealing and have someone run the truck while your under it with mechanincs stethescope and see if you can find what part of the trans the noise is coming from. Pull the front dust cover off and see if there are any wtness marks on anything visible with the motor running and in gear also, good luck Let us know what you find

A noise sometimes described as a squeal or whine is often caused by a rapidly cycling pressure regulator valve (there are a couple of TSB's on this). Factory fix is to replace the valve body but a fluid/filter change will sometimes stop it.

It's more on an annoyance than a real problem.

Thanks for the replies. I would like to know more about this TSB. I do need to remove the front cover and take a better look. I notice now that I have a vibration type noise only when in gear and the squeal is like a rotational scraping noise. But again only when put in gear and not moving. Please keep the ideas coming.

I tried to look up this TSB on a google search. I think i know what your talking about. I had a 96 that made a buzzing sound when cold the first time you would back up in the morning. An oil and filter change solved that. This is much louder and more metal to metal sounding. What all is moving when your stopped and the trans is in drive? Is the pump turning all the time? The outside of the torque converter is turning but not the inside correct? And is that call stalling? Like stall speed?

If the engine is running the trans pump is turning whether it's in gear, neutral or park.

Standing still, in gear - nothing in the trans is turning, reg. valve is maintaining line pressure, TC valve is maintaining converter fill, pump rotors are turning, outside of converter (front cover and impeller) are turning, stator should be locked on the stator shaft, turbine is stationary since it is splined to the input shaft, lock up piston and damper are stationary since they are locked to the turbine, your unit may have a needle bearing between the stator and the impeller or front cover - if not it has a phenolic thrust washer in place of the needle bearing. So - if the noise is there while the vehicle is stationary, it is likely the converter. The fact that it makes more or less noise while moving is just more info - could be the fact that the internals are being loaded more or less by speeding up or slowing down because the stator gets loaded in different ways based on these maneuvers.

Thank you Transman for the details. That was more than i would have ever figured out on my own. So if I understand what you said It could be a needle bearing in/on the stator, Because the internals are not moving when stopped. Now i believe it was said that the pump is running all the time but it all sounds good when driving at speed so its most likely not the pump? I'm going to post a question in the truck section about what people are using for a replacement converter. Please feel free to comment on this issue or share what you are using for a converter.

Any converter properly built is fine for what you are doing. Notice I said properly built/remanufactured. As long as you have the correct stall speed for your application my only suggestion is to add a smaller cooler since you are hauling. Keep the trans fluid around 180-190 degrees (using a quality fluid like ATF + 4) will help durability of the trans and fuel consumption. I doubt you drive this rig when super cold outside - if you do, bypass the cooler for this cold weather operation or run the outlet line from the trans to the radiator first then the cooler.

I had some time this morning to take the front cover off the bell housing. It was surprisingly clean in there. No loose bolts, could not see any cracks. I listened to it again from underneath and the squealing sounds to be right there in the converter. If no one has any other ideas, I guess I will have to pull it out when I have more time and see what I can find...