Loud squeal, loss power

[Wrestlemy69]

Sound is worse when cold or accelerating. If let off accelerator after truck is warm noise goes away. If acelerate more than gradual vehicle loses acceleration. Noise is still present when belt is off. I am no mechanic and am at a total loss. Google is little help. Been to several mechanics. All say something totally different. Any ideas are helpfull.

A bit of back story. The truck is used to tow and launch a boat. (Water damage maybe?)

 

[Karlsweg]

Check the rear end oil?

 

[LoneWolf3574]

Does the squeal come from the front or rear?

 

[Karlsweg]

Does the squeal come from the front or rear?

I’m thinking since it’s been used to unload boats that it could have submerged the rear and there’s water in it and the bearings are making noise. They have undersized pinion bearings (IMO) and they fail. There my be no oil left also (could explain feeling of lost power due to heat expansion). I had a pinion bearing that was screaming but only on acceleration.

 

[Wrestlemy69]

The noise is coming from engine area which is why I removed the belt. Makes the noise when in park and cold. I did crawl under and could not pin point the sound exactly, but my guess is bottom rear of engine area. (May not be engine). I plan on using a garden hose to try and further pin point sound when the weather warms up. As I said I'm not a mechanic or even close and most of my knowledge is learned on the fly through google, which usually leaves me more confused than when I started.

With that being said. Any suggestions on how to go about checking your suggestions would be great. I assume checking the rear end means the differential? Would that cause the sound further up front? If so how does one suggest I check it and its oil?

 

[Karlsweg]

There is a rubber plug on the diff cover. Use a screwdriver to pop it out. Gear oil should be about 1/2 inch below the plug hole. If the noise is up front. It may be the torque converter. Use a screw driver like a stethoscope and put the handle up to your ear and the blade against where you think the noise is coming from. I now assume it makes the noise while idling?

 

[Karlsweg]

Does rpms increase the noise? And does it sound like a power steering whine?

 

[Wrestlemy69]

It sounds like a high pitch belt scream. It does it at idle when it's cold, but once warmed up it does not. Yes and no at higher rpms. It does it constantly until warmed up. Once it is warmed up it only does it when accelerating normally and not babying it. I did not notice any coordination between exact rpm range and noise or loss of power. I Will try and narrow down the noise as well as check the real oil tomorrow. Ty!

 

[RonJon '06]

A few years ago a member here had a cracked exhaust manifold that sounded just like a belt squeal.

 

[Wrestlemy69]

Ok. So it didnt make the noise long on cold start this morning. So I didnt have enough time to narrow down the exact location. But from what I could tell It is coming from the engine near the transmission. I checked the transmission fluid back when the issue first started with no issue. Checked it again today and it was dry. Refilled it. Parked it in an area I can observe leaks. May change out the trans filter next week. (If I can figure out how lol)

Could a transmission cause the sound even though it does it on a cold start?

Checked the rear diff oil and it was fine. About an inch below the hole. Very thick.

I did read where a clogged exhaust system could cause the loss of power and a squeal from the manifold. But I dont smell exhaust in the cab. It's also warm air coming from exhaust pipe.

I recorded a video of driving but cant figure out how to upload it. I only drove in a neighborhood so couldn't reach high speed. But it seemed to squeal loud when I got near 2k rpm.

Any ideas?

 

[Karlsweg]

Yes a low fluid level could make the trans pump whine until fluid pressure is built up. And also could seem like loss of power. If cat is clogged exhaust manifold and pipe would be cherry red.

 

[Karlsweg]

Ps there are 2 filters in trans lol

 

[Jason G Slabaugh]

I was going to guess fan clutch..

 

[Wrestlemy69]

 

[crash68]

torque converter starting to go bad maybe?

 

[Wrestlemy69]

Imo I dont think fan clutch because it makes the sound with out the belt on. Is this a correct assumption?

The converter seems like a possible candidate, but from what I read, the symptoms dont totally line up.

 

[Jason G Slabaugh]

Oops youre right I forgot you took the belt off

 

[Wrestlemy69]

Update

So I replaced the downstream 02 sensor on the driver side. The tip had totally melted and bent its self in half. Later that day I was driving down the road. Hear a small pop and the truck took off like it was brand new and the squeal dissapeared instantly. Truck was driving great for 2 days. Now the squeal is coming back and have a new code 420. I dont really want to drop the Catilac converter but I guess that's my next step.

 

[Karlsweg]

Yeah my o2 sensors were like that and killed the cats.