Loud howling sound need help!!

[96ranger96]

Hey guys I have a 96 ranger 4.0l 4x4 5speed. My slave cylinder was leaking real bad so I replaced it. Took the drive shafts out, tranny mount, exhaust, y pipe, ya know everything to get to the tranny. Swapped slave cylinders and put it back up. Hooked everything up and bled it. Took it for a drive, about 5 miles down the road I hear this loud obnoxious howling. Come to a stop, still doing it for about 10 seconds then stops. Drove around a bit more to try and figure out when it does it and what happens when I do certain stuff. When it would make this loud noise I would engage and disengage the clutch, nope still will keep going. If I shift into neutral it doesn't stop. It will only stop when I, let say, put a load on the truck. If I give it gas, push the clutch in and rev it it stops immediately. I had it in 4th and it started howling, I took my foot off the gas and just let the truck coast in gear. It continued to make the noise until I shifted into 3rd. It happens at any speed although it hasn't above 50 nor at an idle. Happens very random. Anyone have any idea where I went wrong or what it could be? It's so loud I can't pin point it. Hopefully I didn't confuse anyone lol. Any ideas would be great thanks.

 

[RonD]

Have you tried shifting the transfer case thru the gears, maybe it's just not fully engaged.

It doesn't read like input side of trans, i.e. clutch side, since noise is only when tires are moving, so output side, which all goes thru transfer case

 

[96ranger96]

When it makes the noise if I come to a stop it will continue after tires have stopped for only a couple seconds. I would say maybe 10-15 sec. Long enough to know I'm stopped and it's still making the noise but short enough so I can't get out of the truck and pinpoint it. It's just strange. Truck didn't make the noise before I replaced the slave cylinder.

 

[RonD]

If it makes the noise when engine is turning but wheels are not then it would be input side, so yes clutch.

Only "rubbing" parts are pilot bearing and throwout bearing
Throwout bearing usually only makes noise with pedal in, but can "rub" with pedal out
Pilot bearing gets used mostly when pedal is in as well and input shaft RPM is less than engine RPM.

You just replaced slave right?

You didn't put in a new disc without new pressure plate?

 

[96ranger96]

Right. I just replaced the slave cylinder. I didn't even drop tranny all the way just enough to get to the old slave and put the new one on. Didn't touch the clutch. If it was the transfer case how do I go through the gears in it?

 

[RonD]

Transfer case could only make a noise when wheels are moving, so doesn't fit with second description.
Just shift into 4WD hi and lo, then back to 2WD

 

[96ranger96]

Ok so what moves when the truck is in motion and slows down after a few seconds when I stop? Would a throw out bearing or pilot bearing make a loud howling if that was the problem?

 

[RonD]

Either could.
The fly wheel spins at engine speed, pilot bearing is in the fly wheel

The input shaft rides in the pilot bearing.
When you press clutch pedal in you disengage input shaft from flywheel, but input shaft is still spinning at the speed of the gear the transmission is in until you shift it into Neutral or another gear.
If engine RPM was 2,000 and you were in 4th gear(1:1 ratio), output shaft is at 2,000 RPMs
You press clutch pedal in and let off the gas, engine RPM drops to 800 fairly fast but output and input shaft is still dropping from 2,000 as you coast.

Throwout bearing generally would only make a noise when pedal is in, but if the slave wasn't centered input shaft could rub on it or throwout bearing.

In any case I guess you will need to open it up again.
When reinstalling you can damage pilot bearing if alignment tool wasn't used, if you never loosened pressure plate I would expect it to be aligned from previous use, but when you removed trans you may have shifted alignment if it didn't come straight out easily.

 

[96ranger96]

Would a carrier bearing make a howling if it was bad?

 

[RonD]

Would a carrier bearing make a howling if it was bad?

Yes, drive line bearing can may a noise when going bad, but ONLY when wheels are moving, and above about 20mph.
You reported noise after stopping which couldn't be a drive line issue.

 

[alwaysFlOoReD]

I recently saw in another thread where a driveshaft vibration damper broke free from the rubber attachment. I could see that loose piece still spinning after stopping. A long shot....