So if I’m hearing that sound just in cold start, the 2.7 uses forged pistons I think, so there’s the answer.
Rattle back knock .
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I wouldn't even venture a guess without listening to it firsthand. No guarantees without looking at piston skirts and then measuring the pistons and bores. I'm not suggesting this but bearing knock and piston slap can also sound like one another at first. Worn rod bearings soon get a very distinctive sound and are most often noticed at a lower RPM. The second video in this thread was hard for me to hear what I wanted to hear except in one certain spot. It sounded to me like it had some top-end noise (valve-train) but from underneath I could hear a noise that I couldn't distinguish.
Years ago, I was building 400 Ford engines with 351 Cleveland parts. These were real runners they'd put down 500 usable street HP. These engines would really run with large port, big valve, closed chambered heads on them. We tried parts from several manufacturers including cams pistons etc. We had one that was running a TRW Forged Piston/Piston Ring pack.
This engine was built as well as human hands could put it together following parts manufacturers very closely. It developed a noise (later confirmed as piston slap and beyond) very early in its street life, just a couple of thousand miles. I saw serval of these go beyond 70,000 miles (that was respectable back then for a forged piston engine), including my father-in-law's F150 4X4. It had been broken in properly. Its cylinder-to-wall clearance was perfect according to TRW's specs.
This engine was disassembled it had literally broken the skirts in two cylinders but the break (upside-down triangle break) was such that the skirt was still going up and down with the piston. The cylinders were undamaged. After many discussions and mailing some parts back and forth, TRW re-designed this piston including additional skirt ribbing and a "thicker" ring pack. We ended up using custom Mahle's after this happened. I don't know if the problem was resolved.
I'm telling a long story here but the thing is you could barely hear this noise at first and it ended up literally being broken pistons. Without revving it to a couple of thousand RPMs and backing out, most simply couldn't hear it. I couldn't hear it at a sustained RPM. It got louder but it wasn't like it was just slapping one day and broken the next, very subtle over a few weeks' time. These noises don't go away, they'll get louder. I'm sure that's more than any of you wanted to read.
Years ago, I was building 400 Ford engines with 351 Cleveland parts. These were real runners they'd put down 500 usable street HP. These engines would really run with large port, big valve, closed chambered heads on them. We tried parts from several manufacturers including cams pistons etc. We had one that was running a TRW Forged Piston/Piston Ring pack.
This engine was built as well as human hands could put it together following parts manufacturers very closely. It developed a noise (later confirmed as piston slap and beyond) very early in its street life, just a couple of thousand miles. I saw serval of these go beyond 70,000 miles (that was respectable back then for a forged piston engine), including my father-in-law's F150 4X4. It had been broken in properly. Its cylinder-to-wall clearance was perfect according to TRW's specs.
This engine was disassembled it had literally broken the skirts in two cylinders but the break (upside-down triangle break) was such that the skirt was still going up and down with the piston. The cylinders were undamaged. After many discussions and mailing some parts back and forth, TRW re-designed this piston including additional skirt ribbing and a "thicker" ring pack. We ended up using custom Mahle's after this happened. I don't know if the problem was resolved.
I'm telling a long story here but the thing is you could barely hear this noise at first and it ended up literally being broken pistons. Without revving it to a couple of thousand RPMs and backing out, most simply couldn't hear it. I couldn't hear it at a sustained RPM. It got louder but it wasn't like it was just slapping one day and broken the next, very subtle over a few weeks' time. These noises don't go away, they'll get louder. I'm sure that's more than any of you wanted to read.
I wouldn't even venture a guess without listening to it firsthand. No guarantees without looking at piston skirts and then measuring the pistons and bores. I'm not suggesting this but bearing knock and piston slap can also sound like one another at first. Worn rod bearings soon get a very distinctive sound and are most often noticed at a lower RPM. The second video in this thread was hard for me to hear what I wanted to hear except in one certain spot. It sounded to me like it had some top-end noise (valve-train) but from underneath I could hear a noise that I couldn't distinguish.
Years ago, I was building 400 Ford engines with 351 Cleveland parts. These were real runners they'd put down 500 usable street HP. These engines would really run with large port, big valve, closed chambered heads on them. We tried parts from several manufacturers including cams pistons etc. We had one that was running a TRW Forged Piston/Piston Ring pack.
This engine was built as well as human hands could put it together following parts manufacturers very closely. It developed a noise (later confirmed as piston slap and beyond) very early in its street life, just a couple of thousand miles. I saw serval of these go beyond 70,000 miles (that was respectable back then for a forged piston engine), including my father-in-law's F150 4X4. It had been broken in properly. Its cylinder-to-wall clearance was perfect according to TRW's specs.
This engine was disassembled it had literally broken the skirts in two cylinders but the break (upside-down triangle break) was such that the skirt was still going up and down with the piston. The cylinders were undamaged. After many discussions and mailing some parts back and forth, TRW re-designed this piston including additional skirt ribbing and a "thicker" ring pack. We ended up using custom Mahle's after this happened. I don't know if the problem was resolved.
I'm telling a long story here but the thing is you could barely hear this noise at first and it ended up literally being broken pistons. Without revving it to a couple of thousand RPMs and backing out, most simply couldn't hear it. I couldn't hear it at a sustained RPM. It got louder but it wasn't like it was just slapping one day and broken the next, very subtle over a few weeks' time. These noises don't go away, they'll get louder. I'm sure that's more than any of you wanted to read.
I read it .
It was valuable information.
.
this also helps to clarify to me this isn't the form of slap I am seeing here.
I am familiar with the sound of slap from to much clearance, this is only under" piston float conditions".
Something that these automatic f150s don't typically see.
By float I am referring to the exact point where it's not accel. Or decal, just holding rpm with no load.
I stand corrected.I wouldn't even venture a guess without listening to it firsthand. No guarantees without looking at piston skirts and then measuring the pistons and bores. I'm not suggesting this but bearing knock and piston slap can also sound like one another at first. Worn rod bearings soon get a very distinctive sound and are most often noticed at a lower RPM. The second video in this thread was hard for me to hear what I wanted to hear except in one certain spot. It sounded to me like it had some top-end noise (valve-train) but from underneath I could hear a noise that I couldn't distinguish.
Years ago, I was building 400 Ford engines with 351 Cleveland parts. These were real runners they'd put down 500 usable street HP. These engines would really run with large port, big valve, closed chambered heads on them. We tried parts from several manufacturers including cams pistons etc. We had one that was running a TRW Forged Piston/Piston Ring pack.
This engine was built as well as human hands could put it together following parts manufacturers very closely. It developed a noise (later confirmed as piston slap and beyond) very early in its street life, just a couple of thousand miles. I saw serval of these go beyond 70,000 miles (that was respectable back then for a forged piston engine), including my father-in-law's F150 4X4. It had been broken in properly. Its cylinder-to-wall clearance was perfect according to TRW's specs.
This engine was disassembled it had literally broken the skirts in two cylinders but the break (upside-down triangle break) was such that the skirt was still going up and down with the piston. The cylinders were undamaged. After many discussions and mailing some parts back and forth, TRW re-designed this piston including additional skirt ribbing and a "thicker" ring pack. We ended up using custom Mahle's after this happened. I don't know if the problem was resolved.
I'm telling a long story here but the thing is you could barely hear this noise at first and it ended up literally being broken pistons. Without revving it to a couple of thousand RPMs and backing out, most simply couldn't hear it. I couldn't hear it at a sustained RPM. It got louder but it wasn't like it was just slapping one day and broken the next, very subtle over a few weeks' time. These noises don't go away, they'll get louder. I'm sure that's more than any of you wanted to read.
This is starting to sound more like poor piston to bore clearance.
Sweet. And with only 250miles on it!!
🤦🏻♂️
I tried attaching a video so you could here and confirm but it says I don't have allowed extension.
I wouldn't even venture a guess without listening to it firsthand. No guarantees without looking at piston skirts and then measuring the pistons and bores. I'm not suggesting this but bearing knock and piston slap can also sound like one another at first. Worn rod bearings soon get a very distinctive sound and are most often noticed at a lower RPM. The second video in this thread was hard for me to hear what I wanted to hear except in one certain spot. It sounded to me like it had some top-end noise (valve-train) but from underneath I could hear a noise that I couldn't distinguish.
Years ago, I was building 400 Ford engines with 351 Cleveland parts. These were real runners they'd put down 500 usable street HP. These engines would really run with large port, big valve, closed chambered heads on them. We tried parts from several manufacturers including cams pistons etc. We had one that was running a TRW Forged Piston/Piston Ring pack.
This engine was built as well as human hands could put it together following parts manufacturers very closely. It developed a noise (later confirmed as piston slap and beyond) very early in its street life, just a couple of thousand miles. I saw serval of these go beyond 70,000 miles (that was respectable back then for a forged piston engine), including my father-in-law's F150 4X4. It had been broken in properly. Its cylinder-to-wall clearance was perfect according to TRW's specs.
This engine was disassembled it had literally broken the skirts in two cylinders but the break (upside-down triangle break) was such that the skirt was still going up and down with the piston. The cylinders were undamaged. After many discussions and mailing some parts back and forth, TRW re-designed this piston including additional skirt ribbing and a "thicker" ring pack. We ended up using custom Mahle's after this happened. I don't know if the problem was resolved.
I'm telling a long story here but the thing is you could barely hear this noise at first and it ended up literally being broken pistons. Without revving it to a couple of thousand RPMs and backing out, most simply couldn't hear it. I couldn't hear it at a sustained RPM. It got louder but it wasn't like it was just slapping one day and broken the next, very subtle over a few weeks' time. These noises don't go away, they'll get louder. I'm sure that's more than any of you wanted to read.
May 11, 2022
youtube.com
Ok figured out how to transfer information 😆.
I had to use the echo from the building to hear it.
It is only noticeable under the certain criteria I laid out for ya folks.
I have yet to be able to recreate it while driving it like a normal automatic.
And even free revving like I did in this video,I still needed to feather the throttle
If I were to blip it, it won't do it.
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