Need help diagnosing these noises

[Pete Whitstone]

Today I was towing a trailer to pick up some metal. I thought I heard a weird tick that seemed to be in time with engine RPMs, but I wasn't sure. About 2 miles from home, the truck started making a terrible racket, like I was dragging a barbed wire fence or something. I didn't really want to deal with abandoning the trailer and metal (stuff's expensive these days) and getting it towed, so I risked it and drove it the rest of the way home.

To me the clatter sounded kind of sheet-metal-y, so I assumed a rocker had maybe given up, or a broken spring or something. So I pulled the valve covers, everything is fine there. Pulled all the spark plugs, they all looked good. Ran a compression test on all cylinders, all around 150psi. The engine never seemed to struggle and the truck drove normally, just a bunch of noise. After I put the top of the engine back together, I thought it might be a flexplate nut had backed off. Pulled the inspection cover and all looked normal in there.

I started the truck and tried to get a couple of videos of the truck making the noise. The noise seems to be coming from the oil pan or transmission bellhousing area. It seems a bit louder to me by the bellhousing. The torque converter is the original 1995 stock unit, which I'm told were prone to ballooning, but I have no clue what that would sound like, and I thought those problems manifested themselves at high rpms. These videos were taken at idle. Any good guesses, anyone?

In the videos it sounds strongly like a rod knock, but in real life it is different than that. If you listen carefully, there is a kind of screechy component to it, not just a knock. Oil pressure is good and never dropped.

One more thing that might be a clue is that the previous 2 drives to this one, the transmission took its time dropping into gear. I had written this off as it getting cold, reducing the fluid volume, and I needed to add a bit. That may still be what it is, or it might have something to do with what's going on now, I don't know.

[grumpin]

Wow!

First thing I thought of was something on the flex plate was bad, but you checked that.

If the tranny was acting up I would be suspicious. I've never heard a tranny make a noise like that, but it is an E4OD and some have had problems.

I associate E4OD problems with torque, I had a 94 F250 with a 460, with one and it was problematic. I have one in the Bronco and it's great.

I also might think water pump but the noise seems too far back.

I'm not helping, but boy, that sounds terrible!

[ArdWrknTrk]

The audio is really difficult for me to interpret.

If you think it might be coming from the transmission I think the old pry bar handle to the ear 'stethoscope' would pinpoint that as the cause.

Also, id think a transmission noise is going to change with gear or road speed.

If it strictly follows engine speed and gets louder under load i'd suggest you have an exhaust leak.

This also might explain your whistling component.

A few feet of vinyl tube (3/8"? ID) will let you listen close along the flanges and pinpoint a source.

I know that periodically the inside bottom of #8 on my truck will get to leaking, and sound like a bad valve tick.

Good luck Pete. I hope you find it soon.

[Pete Whitstone]

Wow!

First thing I thought of was something on the flex plate was bad, but you checked that.

If the tranny was acting up I would be suspicious. I've never heard a tranny make a noise like that, but it is an E4OD and some have had problems.

I associate E4OD problems with torque, I had a 94 F250 with a 460, with one and it was problematic. I have one in the Bronco and it's great.

I also might think water pump but the noise seems too far back.

I'm not helping, but boy, that sounds terrible!

Good thoughts. Water pump is new-ish, about 2 yo. I replaced it when I built the engine. One of the tests I need to perform is to take off the accessory belt and see if it still clatters. I really don't think that test will prove anything, but I don't want to tear the engine out only to find it was not in the engine itself, so gotta do the due diligence.

This particular E4OD is not highly stressed, torque wise. I am pretty gentle on the throttle, MPG is already in the 10 range so I don't need to make that worse. It was pulling a 2k lb trailer when it happened though, so anything's possible.

I still haven't ruled out a problem with the flexplate. I can only see a little bit of it at a time through the inspection cover. I do wonder if one of the 6 bolts in the crank could have backed out. Guess I would not be able to see that unless I separated the engine and trans. They were loctited and torqued properly, so I don't think that's it, but like I said, anything is possible.

Thanks for the response!

[Pete Whitstone]

The audio is really difficult for me to interpret.

If you think it might be coming from the transmission I think the old pry bar handle to the ear 'stethoscope' would pinpoint that as the cause.

Also, id think a transmission noise is going to change with gear or road speed.

If it strictly follows engine speed and gets louder under load i'd suggest you have an exhaust leak.

This also might explain your whistling component.

A few feet of vinyl tube (3/8"? ID) will let you listen close along the flanges and pinpoint a source.

I know that periodically the inside bottom of #8 on my truck will get to leaking, and sound like a bad valve tick.

Good luck Pete. I hope you find it soon.

I did do the hose trick, but the noise is so loud under there it's difficult to isolate. It did seem louder in the bellhousing than in the pan, but it's hard to say since the bellhousing was open and the pan was closed, so the sound just might be louder because it's got a place to come out.

I'm relatively sure it's not an exhaust leak but I will double check that. Too much clanking going on.

My BIL suggested that the dipstick might have fallen down into the crank, which was a brilliant thought, but that was not it.

I'm stumped by "inside bottom of #8 gets to leaking". #8 is cylinder/piston 8? What and how does it leak?

I think my next move is going to be to see if my snake camera fits in the oil drainplug hole. I have to wonder if some kind of baffle in the oil pan has come adrift. Or maybe I can spot a rod cap coming off or something.

Question: to drop the pan, is that an engine-out proposition? Looks to me like there's only about an inch of clearance between the bottom of the pan and the crossmember. Is it possible to pull the engine up enough to snake the pan out of there, or am I dreaming?

Thanks for the response.

[ArdWrknTrk]

I did do the hose trick, but the noise is so loud under there it's difficult to isolate. It did seem louder in the bellhousing than in the pan, but it's hard to say since the bellhousing was open and the pan was closed, so the sound just might be louder because it's got a place to come out.

I'm relatively sure it's not an exhaust leak but I will double check that. Too much clanking going on.

My BIL suggested that the dipstick might have fallen down into the crank, which was a brilliant thought, but that was not it.

I'm stumped by "inside bottom of #8 gets to leaking". #8 is cylinder/piston 8? What and how does it leak?

I think my next move is going to be to see if my snake camera fits in the oil drainplug hole. I have to wonder if some kind of baffle in the oil pan has come adrift. Or maybe I can spot a rod cap coming off or something.

Question: to drop the pan, is that an engine-out proposition? Looks to me like there's only about an inch of clearance between the bottom of the pan and the crossmember. Is it possible to pull the engine up enough to snake the pan out of there, or am I dreaming?

Thanks for the response.

I'd think you would see some metallic flakes or a really shiny bolt head if a flex plate bolt had backed out (and become a crude fly cutter)?

You can poke the hose around from the top where you're not surrounded by noises.

The metal lamination of an exhaust gasket can screech like a blade of grass between your thumbs when you blow through it.

My initial probing had me thinking my tick or clatter might be coming from the LH headpipe to manifold junction, but working with a cold engine so I didn't burn my hand it became very clear that it was the bottom of the #8 exhaust port nearer the side facing #7.

Don't discount the old screwdriver to the ear trick or even an actual mechanics stethoscope with a solid wand.

These are cheap enough at places like harbor freight.

If the noise is coming from inside a case or block you will know right away.

 

[ArdWrknTrk]

Question: to drop the pan, is that an engine-out proposition? Looks to me like there's only about an inch of clearance between the bottom of the pan and the crossmember. Is it possible to pull the engine up enough to snake the pan out of there, or am I dreaming?

Gary said it was possible to get Brandon's 4x4 351 pan out with the engine in place but that it took the lift, a transmission jack and both of them all day to swap his oil pump.

Also that he would never again waste his time as it's easier and quicker to pull the engine (in the Garagemahal)

I can't really speak about doing it with a Windsor.

With a 4x4 460 or 420 IDI definitely not happening.

[Gary Lewis]

Question: to drop the pan, is that an engine-out proposition? Looks to me like there's only about an inch of clearance between the bottom of the pan and the crossmember. Is it possible to pull the engine up enough to snake the pan out of there, or am I dreaming?

Gary said it was possible to get Brandon's 4x4 351 pan out with the engine in place but that it took the lift, a transmission jack and both of them all day to swap his oil pump.

Also that he would never again waste his time as it's easier and quicker to pull the engine (in the Garagemahal)

I can't really speak about doing it with a Windsor.

With a 4x4 460 or 420 IDI definitely not happening.

Amen, Brother!!!

[mat in tn]

I did do the hose trick, but the noise is so loud under there it's difficult to isolate. It did seem louder in the bellhousing than in the pan, but it's hard to say since the bellhousing was open and the pan was closed, so the sound just might be louder because it's got a place to come out.

I'm relatively sure it's not an exhaust leak but I will double check that. Too much clanking going on.

My BIL suggested that the dipstick might have fallen down into the crank, which was a brilliant thought, but that was not it.

I'm stumped by "inside bottom of #8 gets to leaking". #8 is cylinder/piston 8? What and how does it leak?

I think my next move is going to be to see if my snake camera fits in the oil drainplug hole. I have to wonder if some kind of baffle in the oil pan has come adrift. Or maybe I can spot a rod cap coming off or something.

Question: to drop the pan, is that an engine-out proposition? Looks to me like there's only about an inch of clearance between the bottom of the pan and the crossmember. Is it possible to pull the engine up enough to snake the pan out of there, or am I dreaming?

Thanks for the response.

it is really difficult to hear well enough to diagnose but it does seem to be torque converter centered. I wonder about a failure in that. not that I think it's a common thing. just that it does not seem to be as repetitive as a rod bearing or a cracked flex plate flexing. more like rotationally random. in fact, it does sound like a broken exhaust hanger in a way.

[mat in tn]

it is really difficult to hear well enough to diagnose but it does seem to be torque converter centered. I wonder about a failure in that. not that I think it's a common thing. just that it does not seem to be as repetitive as a rod bearing or a cracked flex plate flexing. more like rotationally random. in fact, it does sound like a broken exhaust hanger in a way.

on a second note. pull the engine to gain access to the pan. ironically this was just tried today. now the engine is getting pulled in the morning. I tried to say this, but I guess the guys needed to see for themselves. sad thing is that we were firing a fresh rebuild and after 15 min running to set the cam a rocker started tapping and oil pressure went away. so tomorrow to forensics begin.