I got my transmission rebuilt because I had some fluid changed and they found a lot of shavings and chunks (this after I left off 2nd gear and it would buck forward) - I was worried it would blow and I'd get stranded, so i got a rebuild.

Almost immediately when I get back home, I noticed this squeal noise at idle. It only happens in D, R, 2, and 1. P and N make no noise.

Trans shop said "sounds like an idler pulley to me" which is such a lie, but those are so easy to change I did it anyway. Surprise - no difference. Belt is also pretty new too.

I am wondering if this is the torque converter. Truck drives just fine and shifts fine, I've put 1K on it, but....what the hell is making this noise?

 

COLD ENGINE
Remove fan belt from crank pulley

Start engine, battery light will stay on thats OK
Put trans in gear and see if it squeals
If so take it back to shop

If not then one of the belt pulleys is making the noise

You can run a COLD ENGINE with no water pump for 2 minutes and 2 minutes ONLY

 

Thanks for the suggestion! I'd be happy if it's a pulley vs. something transmission related from the shop

 

Well - bit of a problem. I started the engine cold this AM...no noise. Tried it again this evening, no noise. Drove it around....the noise came back.

This noise only happens when the engine is warmed up - it is OK to run the engine without a belt for even a VERY short time? (I'm talking 10-15 seconds)

 

Yes, that would be fine, even 30 seconds, there is no Load on the engine so it doesn't heat up that fast

With the fan off engine bay will be VERY QUIET, you will be surprised how quiet, lol, so easy way to pin point an engine or trans noise, vs Belt noise

 

Got around to removing the belt, doing the test and...... the noise appears in D and R - I can now officially rule out belts as being the issue for this.

Getting under the truck while in Drive (chocked the wheels), the sound is coming from under the truck vs. the engine bay so I feel like this would absolutely be the transmission.

 

Is this the same noise: www.youtube.com/watch?v=nh4AYvVSvjA

 

That's a much louder noise for sure, mine just sounds like a squealing belt but from the transmission. It also only does it in D,R,2,1 like the video does. I feel like my issue could be a bad torque converter like this video.

 

Yes, yours is probably just getting started making the noise
The thing about noises is they tend to get louder as time goes by, like children or wives..........oops, did I say that out loud.....nevermind

 

Well got an answer - during my rebuild, I also threw in a new valve body from Central Valve Bodies to eliminate the 2-3 flare

Bad news - truck shifts fine, but during the teardown at the shop, it wasn't the torque converter, it was the EPC solenoid making that noise.

Truck is back together and drives fine, but that's super frustrating to have to a valve body that is supposed to fix one problem now make a constant noise at idle and D and R.