mbomberz1

So I have about 50 miles on my 3.4 swap. This morning after going for a short 5 mile drive I pulled into the driveway and heard this squeak/squealing noise develop. I had to get to work so I shut it down and headed out. Tonight after work I started up the truck and there was no noise, everything seemed fine, so I went for a 10 mile drive, took it on the freeway, around town and whatnot. No noise. Pull into the driveway again, and the squeak/squeal starts up again.

• New clutch
• new throw out bearing
• new pilot bearing
• rebuilt trans
• rebuilt engine
• lubed up the bearing and related surfaces during assembly

It almost sounds like it is the throwout bearing to me except that it doesn't go away when you step on the clutch. The squeal is sort of intermitten at times and did fade away and come back at one point while I was crawling around the truck with the stethoscope.

• Changes pitch slightly when I depress the clutch
• sometimes fades away with clutch partially engaged, not consistent
• revving up the engine makes it go away until it settles at idle for a few seconds
• using a stethescope, the noise was clearly pinpointed in the bellhousing
• putting trans in gear does not change anything while stopped except for the similar pitch change when using the clutch

This is confusing to me because I am familiar with the throw out bearing making noise when you have a load on it, but not when your just idling stopped out of gear with no pressure on the clutch. Seems to only partially fit the throw out bearing typical diagnosis. I even pushed the clutch fork and slave cylinder farther into the released state and it didnt help, just making sure there was no slight pressure on the plate.

What do you guys think? Any opinions would be appreciated, not too excited at the idea of pulling the trans again.

Here is a video of the noise:

Co_94_PU

iTrader: (-1)

Something is bent warped or misaligned, it sound farther out than the bearing if that makes sense for you. You'll find the obvious wear mark i expect once you get into it.

condolences.

vital22re

iTrader: (2)

I wonder if you damaged the pilot bearing when installing it. On the other hand, I've seen new parts fail on the test drive. Looks like you're going to need to pull the transmission to find the noise.

mbomberz1

I sure hope it is nothing too serious.. going to wait it out a little longer and see if anything else develops. Its being really random.

I was pretty careful when I put in the pilot bearing, found the perfect sized socket and tapped er in with little trouble, but I did have a bit of trouble getting the trans lined up, maybe I tweaked it then. But thinking it over, correct me if I am wrong, the pilot bearing should not be able to make any noise when its sitting there idling in neutral correct? I dont think its even moving at that time because the clutch is engaged, spinning the input shaft along with the flywheel, so everything should be moving at the same speed? That is why my head keeps going back to throwout bearing since part of it should always be moving. It would be really unfortunate if the throwout bearing went south in the first 50 miles, but if it does keep getting worse, that is kind of best case scenario compared to something more catastrophic like me screwing up the clutch or input shaft or who knows what else.

It was squealing pretty good today until I went out and took it on a good 30 mile drive to try and get my catalyst monitor set to ready, which thankfully happened. Since that drive it hasnt made any noise, so I will just keep my fingers crossed for now and report back if anything develops.

Thanks for the input guys.

vital22re

iTrader: (2)

You know what, I just had a thought. Who did the crossover pipe? I've seen it before where exhaust can make squealing noises. That's another thing to check is the crossover to make sure its not rubbing on any heat shields like the one right over the firewall on the driver side.

mbomberz1

Good idea vital, I will double check the clearances on everything back there. I made the crossover myself from all new pipe since my engine had the newer style hydro formed double walled hunk of metal, not the older stye you could just cut up and flip around. It fits pretty good, but definitely worth checking out again. Thanks for the idea. Ill report back.

A little update about the noise itself, its very intermittent, varies in loudness and definitely changes pitch with RPM. I am going on a little trip this weekend with the truck to get some miles on it, so I am going to monitor the noise and if it persists I will try to take another video of it. I know I am going to have to pull the trans again if it does.. but still holding out a little bit of hope that it wont come to that

Here is a shot of the crossover getting installed:

Charchee

I've heard such noises after a new clutch job in one of my big trucks but a shot of grease to the throwout bearing usually does the trick. You don't have that option though. May just be a little piece of debris that stuck in there when you installed it. I wouldn't worry too much yet. If it were one of my work trucks, I'd send it out for a full day's work before I tore anything down. However, if it were one of my Runners, I'd just hang my head and worry about it for a week. It's going to be ok though. Hope it just goes away.