I'm posting this here instead of thread jacking more threads posted by others, especially since most of them are not 4.6 F150s. The videos below are the sound my engine is making. I'm lsowly going through the troublsehooting process to figure out what it is, based on multiple other threads on the topic. I'll update once the issue is corrected.

 

We don't all hear it the same.
My sound system is very wide band stero and produces a lot of of lows.
Most of what I hear is low frequency rumble.
What are you hearing that concerns you?
Guessing in not that helpful.
Good luck.

 

No worries - the video compression really screwed up the sound, so mostly you hear the magnaflow muffler. In the "raw" video, the sound is really noticeable. I'll see if I can't upload it. It's "kind of" like the noise the power steering system makes when it's low on fluid but way louder. I'll try to get a video with the hood up. Problem is that it only does it when it's cold, and I doubt my neighbors would appreciate 5 a.m. truck revving noises.

 

Check your tensioner pully. Mine did the power steering pump sound and I changed it and was still there. Changed the tensioner and idle pully and it was the problem!

 

Yeah - the pulleys were my next step before swapping the PS pump. Untensioned the belt and the tensioner sounded fine. The idler sounded off to me but the wife said she couldn't hear anything. Usually that's only when I'm talking...

Pulled the idler and spun it on my finger and it felt like a bag of marbles. No sound, but really crunchy feeling - not at all smooth like it should be. I'll know for 100% tomorrow morning when I fire it up after it sits overnight. For some reason, once it's been run in a day it doesn't make the sound, so I'm stuck waiting.....

 

Idler pulley FTW! I'll update the description in YT later.

Keywords for search:

screech, grinding, power steering pump, odd noise, weird grinding noise

 

As a follow up, when I finally was able to start and drive the truck in the early morning, there was definitely still a low volume whine/revving noise, but nothing like before. This sound, however, was very familiar to me. My old 79 LeBaron used to make the same noise, and as it got worse, so did my trans. To the point where it shuddered with every shift when cold, and also had no reverse.

I dropped the pan today and that was some nasty smelling stuff in there!! Also, when I dropped the filter, nothing was coming out the bottom port, but when I tipped it over, a whole lot more fluid came out, so it seems that the filter was probably clogged. And, when I finally poured the old fluid into a container, the factory plug was in the bottom, meaning that this is the first time the filter's been changed in 164K miles. It's been flushed before, I am sure, cause I did it at least once, bu the pan's never been off apparently.

Here's a pic of what the magnet in the pan looked like:



Yes, that was a big ball of nasty greasy sludge on there. As I was cleaning the pan, I saw this sticker on the outside of it:



I'm going to look up that TSB, but has anyone seen this before?

So I'm 99% certain the noise will be gone when I fire the truck up tomorrow, I just hope that there are no leaks from the pan.

 

It's right here on FTE:

98-4-12***TRANSMISSION - 4R70W - SERVICE PROCEDURE FOR ORANGE SERVICE TAGGED TRANSMISSIONS

My understanding years ago was that the tagged transmissions were data-logged, and if anything went wrong with them in a short time period, QA at the trans factory wanted to know.

I had ordered a 1997 early in 1996, it took forever to be built and sent to me ( I think it was the first run of 1997 SuperCab Long-Beds at the Norfolk VA. AP). After I put 150 miles on it, 4th gear disappeared... when it shifted up to OD (4th) it just free-wheeled. I had to lockout OD to be able to drive it. Back at the dealer they saw it was tagged, and called the hotline. They told the dealer not to do ANYTHING to it, they were sending a new trans out, and to put the original trans into the shipping carrier of the new one and send it back to them. I assume they would diagnose it and dissect it.

No problems after that, but of course as soon as I got it home I crawled under and looked it over, some (dealer) nitwit routed the harness to the O2 sensors the wrong way round, luckily it didn't rip. I unplugged it and routed it correctly like the factory had it. It was so friggin' obvious, duh!

I have always suspected that the problem was an electrical one, and pulling the trans was an over-reaction. But if the factory wants to get good data to be able to close the loop on problems, they can't have other people pushing and poking around or the samples will be "polluted". A relative of mine was a big honcho at a giant auto manufacturer, and he would talk no end about the "idiots at the dealerships" who "screwed everything up". His words, not mine... However, I certainly have had some bad experiences at dealers. The 1970s and early 80s were awful. After they sold you the car, they didn't want to see it back, go away, or better yet, go up to the showroom and trade it in for the new one, "they're much better".